DHE 18/21/24 - Boiler STIEBEL ELTRON - Free user manual and instructions

Product type	Electric instantaneous water heater
Brand	Stiebel Eltron
Model	DHE 18/21/24 (adjustable 18/21/24 kW)
Dimensions (H x W x D)	466 x 225 x 116 mm
Weight	3.1 kg
Power supply	3/PE ~380-415 V, 50/60 Hz
Connected load	18 / 21 / 24 kW (selectable via jumper)
Temperature range	OFF, 20 °C to 60 °C (in 0.5 °C increments)
Protection rating	IP 25 (IP 24 in horizontal installation)
Maximum admissible pressure	1 MPa (10 bar)
Maximum incoming water temperature	55 °C (supplementary heating), 70 °C max. (disinfection)
Starting flow rate	> 2.5 l/min
Nominal capacity	0.4 l
Protection class	1
Housing material	Synthetic materials
Color	White
Main functions	Electronic regulation, motorized valve, ECO function (3 levels), Tmax limitation, wellness shower programs (4), automatic quantity regulation, consumption display, temperature memory, control lock
Safety	Internal anti-scald protection (adjustable by installer), safety limiter, safety switch, air detection
Cleaning and maintenance	Cleaning with damp cloth, descaling of aerators, cleaning of cold water inlet filter
Spare parts and repairability	Functional modules, sensors, motorized valve, control unit, safety limiter, flow sensor; accessories: radio remote control, load shedding relay, thermostatic mixer, mounting kits
General information	Domestic use, can supply several draw-off points, suitable for shower (shower mode with limitation to 55 °C), vertical or horizontal installation, CE compliant

Frequently Asked Questions - DHE 18/21/24 STIEBEL ELTRON

What to do if the device does not heat up while water is flowing?

First check the circuit breakers. If the power supply is correct, the flow rate may be insufficient (< 2.5 l/min) due to a calcified aerator or a dirty filter. Clean the aerator and the filter. If the problem persists, contact an installer.

How to adjust the set temperature?

Turn the adjustment knob on the console. The temperature can be set between OFF and 60 °C in 0.5 °C increments. You can also memorize two favorite temperatures on the 1 and 2 buttons by pressing for more than 3 seconds.

How to activate the ECO function to save water?

Access the Settings menu by pressing the i button for more than 5 seconds. Navigate to P 1 and select the desired level: ECO1 (8 l/min), ECO2 (7 l/min) or ECO3 (6 l/min). To deactivate, choose OFF.

Is the device protected against burns?

Yes, the installer can set an internal anti-scald protection (position 43, 50, 55 or 60 °C). In shower mode, the temperature must be limited to 55 °C max. The user can also activate the Tmax limitation in the P2 menu for additional safety.

Can I use the device with preheated water (solar)?

Yes, but if the incoming temperature exceeds the setpoint, the water will not be heated and the display will flash. To avoid any risk of burns, install a centralized thermostatic mixer (e.g. ZTA 3/4) set to 55 °C max.

How to clean the cold water inlet filter?

Close the 3-way shut-off valve. Unscrew the cold water connection, remove the filter, clean it with clear water and reassemble. Make sure to replace the gasket and plastic washer correctly.

What do the indicator lights (LED) on the electronic board mean?

Flashing green LED: device powered on. Yellow LED on: heating mode. Flashing yellow: power limit reached. Red on: fault. In case of red, consult the Troubleshooting chapter in the manual.

How to reset the device to factory settings?

In the Settings menu (P10), when rSEt is displayed, press simultaneously the 1 and 2 buttons for more than 5 seconds. The screen displays On, then confirm by pressing i for more than 5 seconds.

What is the minimum height required for installation?

Respect a minimum distance of 50 mm above and below the device, and 90 mm on the sides for easy access. The installation must be vertical, unless horizontal installation is intended (with a condensate drainage hole).

Is the device suitable for a shower?

Yes, it is suitable. The installer must set the internal anti-scald protection to 55 °C max. and use the shower mode. The device can also offer wellness programs (menu P3) with hot/cold alternation.

USER MANUAL DHE 18/21/24 STIEBEL ELTRON

20^ 60^ 0,5^ 68^ F... 140^ 1^

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BEDIENUNG | INSTALLATION

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www.stiebel-eltron.com/registration

INSTALLATION

8. Sicherheit

Diagram showing three stages of a mechanical device with labeled parts and directional arrows indicating motion or assembly.

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Architectural floor plan showing room layouts and equipment layout (no text or labels)

1.1 Safety instructions 59

1.2 Other symbols in this documentation 60

1.3 Units of measurement 60

1. Safety 61

2.1 Intended use 61

2.2 General safety instructions 61

2.3 Test symbols 62

2.4 EU Declaration of Conformity 62

1. Appliance description 62

2. Settings and displays 63

4.1 User interface 63

4.2 Display symbols 64

4.3 Selecting the set temperature 64

4.4 Temperature limit via internal anti-scalding protection (qualified contractor) 65

4.5 Temperature limit Tmax (user) 65

4.6 Assigning temperature memory buttons 65

4.7 Inlet temperature information 65

4.8 Info menu 65

4.9 Settings in the parameter menu 66

4.10 Recommended settings 70

1. Cleaning, care and maintenance 70
2. Troubleshooting 71

INSTALLATION

1. Safety 72
   7.1 General safety instructions 72
   7.2 Shower operation 72
   7.3 Instructions, standards and regulations 72
2. Appliance description 73
   8.1 Standard delivery 73
   8.2 Accessories 73
3. Preparation 74
   9.1 Installation site 74
   9.2 Minimum clearances 75
   9.3 Water installation 75
4. Installation 76
   10.1 Standard installation 76
5. Commissioning 81
   11.1 Preparation 81
   11.2 Initial start-up 82
   11.3 Recommissioning 84
6. Appliance shutdown 84
7. Installation alternatives 84
   13.1 Electrical connection from above on unfinished walls_85

CONTENTS

13.2 Electrical connection on unfinished walls from below with short power cable 86

13.3 Electrical connection on finished walls 86

13.4 Connecting a load shedding relay 87

13.5 Water installation on finished walls 87

13.6 Water installation on finished walls with solder/press fittings 88

13.7 Fitting appliance cover for water installation on finished walls 88

13.8 Lower back panel section installation with threaded fittings on finished walls 89

13.9 Wall mounting bracket when replacing an appliance_90

13.10 Installation with offset tiles 90

13.11 Rotated appliance cover 91

13.12 Operation with preheated water 91

13.13 Horizontal installation of the appliance 92

1. Service information 93

2. Troubleshooting 94

15.1 Fault code display 96

1. Maintenance 97

2. Specification 98

17.1 Dimensions and connections 98

17.2 Wiring diagram 99

17.3 DHW output 100

17.4 Application areas / conversion table ____ 100

17.5 Pressure drop 101
17.6 Fault conditions 101
17.7 Energy consumption data 101
17.8 Data table 102

GUARANTEE

ENVIRONMENT AND RECYCLING

SPECIAL INFORMATION

• The appliance may be used by children over 3 years of age and persons with reduced physical, sensory or mental capabilities or a lack of experience and expertise, provided that they are supervised or they have been instructed on how to use the appliance safely and have understood the potential risks. Children must never play with the appliance. Cleaning and user maintenance must not be carried out by children without supervision.

• During operation, the tap can reach temperatures up to 70 °C. There is a risk of scalding at outlet temperatures in excess of 43 °C.

• The appliance is suitable for supplying a shower (shower operation). If the appliance is also or exclusively used for shower operation, the qualified contractor must adjust the temperature setting range to 55 °C or less using the internal anti-scalding protection on the appliance. When using preheated water, ensure that the inlet temperature does not exceed 55 °C.

• Ensure the appliance can be separated from the power supply by an isolator that disconnects all poles with at least 3 mm contact separation.
• The specified voltage must match the power supply.
• The appliance must be connected to the earth conductor.

OPERATION

General information

• The appliance must be permanently connected to fixed wiring.
• Secure the appliance as described in chapter "Installation / Installation".
• Observe the maximum permissible pressure (see chapter "Installation / Specification / Data table").
• The specific water resistivity of the mains water supply must not be undershot (see chapter "Installation / Specification / Data table").
• Drain the appliance as described in chapter "Installation / Maintenance / Draining the appliance".

OPERATION

1. General information

The chapters "Special information" and "Operation" are intended for both users and qualified contractors.

The chapter "Installation" is intended for qualified contractors.

Note

Read these instructions carefully before using the appliance and retain them for future reference.

Pass on these instructions to a new user if required.

1.1 Safety instructions

1.1.1 Structure of safety instructions

KEYWORD Type of risk

Here, possible consequences are listed that may result from failure to observe the safety instructions.

▶ Steps to prevent the risk are listed.

OPERATION

General information

1.1.2 Symbols, type of risk

Symbol Type of risk

Injury

Electrocution

Burns (burns, scalding)

1.1.3 Keywords

KEYWORD Meaning

DANGER Failure to observe this information will result in serious injury or death.

WARNING Failure to observe this information may result in serious injury or death.

CAUTION Failure to observe this information may result in non-serious or minor injury.

1.2 Other symbols in this documentation

Note

General information is identified by the adjacent symbol. ▶ Read these texts carefully.

Symbol Meaning

Material losses

(appliance damage, consequential losses and environmental pollution)

Appliance disposal

This symbol indicates that you have to do something. The action you need to take is described step by step.

1.3 Units of measurement

Note

All measurements are given in mm unless otherwise stated.

OPERATION

Safety

2. Safety

2.1 Intended use

This appliance is suitable for heating domestic hot water or for reheating preheated water. The appliance can supply one or more draw-off points.

Water will not be reheated if the maximum inlet temperature for reheating is exceeded.

The appliance is intended for domestic use. It can be used safely by untrained persons. The appliance can also be used in non-domestic environments, e.g. in small businesses, as long as it is used in the same way.

Any other use beyond that described shall be deemed inappropriate. Observation of these instructions and of the instructions for any accessories used is also part of the correct use of this appliance.

2.2 General safety instructions

CAUTION Burns

During operation, the tap can reach temperatures up to 70 °C. There is a risk of scalding at outlet temperatures in excess of 43 °C.

CAUTION Burns

If children or persons with limited physical, sensory or mental capabilities use the appliance, set a temperature limit. Once set, check the temperature limit is working correctly.

If a permanent and unchangeable temperature limit is required, have the internal anti-scalding protection set by a qualified contractor.

CAUTION Burns

If operating with preheated water, e.g. if using a solar thermal system, observe the following information:

• The DHW temperature may exceed the set temperature or a set temperature limit.
• The dynamic anti-scalding protection between the appliance and a wireless remote control may not be effective.

▶ In such cases, limit the temperature with an upstream central thermostatic valve (e.g. ZTA 3/4).

OPERATION

Appliance description

WARNING Injury

The appliance may be used by children over 3 years of age and persons with reduced physical, sensory or mental capabilities or a lack of experience and expertise, provided that they are supervised or they have been instructed on how to use the appliance safely and have understood the potential risks. Children must never play with the appliance. Cleaning and user maintenance must not be carried out by children without supervision.

Material losses

The user should protect the appliance and its tap against frost.

2.3 Test symbols

See type plate on the appliance.

2.4 EU Declaration of Conformity

Note

DHE: STIEBEL ELTRON hereby declares that the radio equipment type complies with Directive 2014/53/EU. The full text of the EU Declaration of Conformity can be found at the following internet address: www.stiebel-eltron.de/downloads

3. Appliance description

The appliance switches on automatically as soon as you open the hot water valve on the tap. When you close the tap, the appliance switches off again automatically.

The appliance heats water as it flows through it. The set temperature is adjustable. Upwards of a certain flow rate, the control unit selects the required heating output, subject to the temperature selected and the cold water temperature.

The instantaneous water heater with full electronic control and automatic output matching maintains a consistent outlet temperature. The fully electronic control unit with motorised valve ensures the water is accurately heated to the selected temperature. This occurs regardless of the inlet temperature.

If the appliance is operated with preheated water and the inlet temperature exceeds the selected temperature, the inlet temperature is indicated on the second display line and flashes. The water is not heated further.

You can store different set temperatures and call them up quickly. In the ECO function, the integral motorised valve limits the flow rate to 3 preset levels. The appliance has setting options for a temperature limit (Tmax function, user) and internal anti-scaling protection (qualified contractor). The backlight switches on automatically as soon as water starts to flow through the appliance or you make a change on the user interface. The backlight switches off automatically after water stops flowing or if no action is performed.

OPERATION

Settings and displays

Heating system

The bare wire heating system is enclosed within a pressure-tested plastic jacket. The heating system with its stainless steel heater spiral is suitable for hard and soft water areas and is largely in-susceptible to scale build-up. The heating system ensures rapid and efficient DHW provision.

Note

The appliance is equipped with an air detector that largely prevents damage to the heating system. If, during operation, air is drawn into the appliance, the appliance shuts down heating output for one minute to protect the heating system.

4. Settings and displays

4.1 User interface

375° 125- 4 3 1 2 + 1 5 6 7 8 D0000091079

1 Selector
2 ON LED
3 Temperature memory keys
4 Backlit display
5 Main display | info display | parameter display
6 Segment display [10 - 100 %]
7 Second display line
8 "i" button to call up information and select menus

OPERATION

Settings and displays

4.2 Display symbols

The symbols are shown on the display when activated.

7 8 80.00 °C °F m² gpm 1/min AM kWh PM x1000 gal 1 2 6543 D000073618

1 Wellness showers
2 Automatic water volume control
3 ECO display
4 Tmax, displayed when temperature limit is enabled
5 Consumption indicator
6 Time
7 Operating lock [ON / OFF]
8 Spanner symbol, appears in the event of a fault

4.3 Selecting the set temperature

375°C 125- ① ② ① ① - + 1 D000091079

1 Set temperature settings: OFF, 20 - 60 °C
2 To call up/assign preferred temperatures

Settings

Setting Step Setting Step

20 °C ... 60 °C 0.5 °C 68 °F ... 140 °F

1°F

D000091079

4.4 Temperature limit via internal anti-scalding protection (qualified contractor)

If required, the qualified contractor can set a permanent temperature limit, for example in nurseries, hospitals, etc.

OPERATION

Settings and displays

When supplying a shower, the appliance temperature setting range must be adjusted by the qualified contractor to 55 °C or less. If the anti-scalding protection function is enabled and the temperature limit is reached, "Tmax" flashes.

4.5 Temperature limit Tmax (user)

You can adjust the temperature limit individually. If the temperature limit is enabled, "Tmax" is shown on the display.

4.5.1 Activating/deactivating the temperature limit Tmax

See chapter "Settings in the parameter menu".

4.6 Assigning temperature memory buttons

Memory buttons "1" and "2" can each be assigned a preferred temperature.

▶ Select the preferred temperature.

▶ To save the preferred temperature, press and hold button "1" or "2" for more than 3 seconds. The selected temperature flashes once to confirm.

4.7 Inlet temperature information

If the appliance is operated with preheated water and the inlet temperature exceeds the selected set temperature, the inlet temperature is indicated on the second display line and flashes. The water is not heated further.

4.8 Info menu

The appliance has an additional display where consumption values can be shown.

4.8.1 Calling up the info menu

▶ Briefly press "i" until "i 1" appears, then continue to press "i" to see further menus.
▶ Exit the menu item by pressing "i" and holding for more 5 seconds. Alternatively: The system exits the menu item automatically 30 seconds after the setting has been completed.

Menu	Description	Explanations	Screen | display
1 1	Flow rate The current flow rate is shown.	flow rate is shown.	Flow rate in l/min or gpm
1 2	Time The current time is shown.	The current time is shown.	Time
1 3	Energy consumption The amount of energy consumed is shown.	The amount of energy consumed is shown.	Value in kWh
1 4	Water consumption The amount of water consumed is shown.	The amount of water consumed is shown.	Value in m^3 or gal

Note

The consumption values are calculated starting from the last reset.

OPERATION

Settings and displays

4.9 Settings in the parameter menu

4.9.1 Activating the parameter menu

▶ Briefly press and hold "i" for more than 5 seconds until "P 1" appears, then continue by briefly pressing "i".
▶ In the selected parameter menu, turn the temperature selector to the required display / setting.

4.9.2 Parameter menu

Menu	Description Selectable display | setting		Explanations Symbol |	display
P 1	ECO water and energy saving function	OFF | ECO1 | ECO2 | ECO3	The ECO function enables you to limit the flow rate to a maximum value. Flow rate limit:8 l/min with "ECO1" | 7 l/min with "ECO2" | 6 l/min with "ECO3" | No flow rate limit with "OFF".
P 2	Temperature limit Tmax	OFF | 20.0 | 20.5 ... °C or 68 | 69 ... °F	The temperature limit allows you as a user to restrict the adjustable set temperature at the appliance to a maximum value. Check that the upper temperature limit has been correctly applied. Your qualified contractor can set an additional temperature limit for anti-scalding protection. This temperature then dictates the upper limit of the setting range for the temperature limit function.	Tmax

OPERATION

Settings and displays

Menu	Description Selectable display | setting	Explanation Symbol |	display
P 3	Wellness showers	OFF | Pro1 | Pro2 | Pro3 | Pro4	The Wellness shower program lets you choose from 4 different alternating shower programs.WW = domestic hot water, KW = cold water, min = minutes, sec = seconds- 1 Cold preventionTo strengthen the body, we recommend finishing off with a cold shower; this will trigger a reflex in the body to warm up.____- 2 Winter refreshmentAn invigorating end to a winter shower with a final warm-up.____- 3 Summer fitness programA quick contrast shower to increase fitness with a final warm-up.____- 4 Circulation boost programShower your arms and legs with cold water to boost circulation. Spray from the hands and feet towards the body. You can then repeat this process with hot water.____

OPERATION

Settings and displays

Menu	Description Selectable display | setting		Explanations Symbol |	display
P 4	Automatic water volume control - set the volume in the selected unit	OFF | 5 | 10 | ... 200 | or 2 ... 52 gal	With the automatic water volume control, you can preselect a volume of water, e.g. for filling a bathtub. When the preselected water volume is reached, the automatic control reduces the flow rate. The automatic water volume control must be enabled on each occasion prior to filling the bath.Example, filling a bath with 80 litres (21 gallons): When the bath has been filled with 80 litres (21 gallons), the control automatically reduces the flow rate to 4 l/min (1 gpm).
P 5	Temperature unit	C | F	Select the temperature unit for all settings.	°C | °F
P 6 Volume unit L | GAL Select the volume unit for all settings. | | gal
P 7 Time format 24h | 12h		Select time format.		◎
P 8	Time setting	---:--	You can set the time using the 12 or 24 hour clock:- 12 hours from 00:00 - 11:59 = AM | 11:59 - 00:00 = PM- 24 hours from 00:00 to 23:59After a power cut, the time needs to be set again.	AM | PM (only for 12h)
P 9	Operating lock	ON | OFF	You can set the operating lock to "ON" or "OFF".To disable the set operating lock:► Press and hold "i" for more than 12 seconds.	◎ (only when ON)
P 10	Reset to factory settings	Reset (rSEt)	You can restore the appliance to its factory settings. "rSEt" is shown on the display.► Press "1" and "2" simultaneously and hold for longer than 5 seconds. The display switches to "On" to confirm the reset.► To confirm "On", press and hold "i" for more than 5 seconds.
P 11	Resetting the consumption values	Reset (rSEt | □)	You can reset the consumption values. "rSEt" is shown on the display.► Press "1" and "2" simultaneously and hold for longer than 5 seconds. The display switches to "On" to confirm the reset.► To confirm "On", press and hold "i" for more than 5 seconds.

OPERATION

Settings and displays

Menu	Description Selectable display | setting		Explanations Symbol |	display
P 12	Backlighting	Auto | On	You can adjust the display backlight.- If "Auto" is selected, the backlight is switched on during heating operation and each time an action is performed. If no action is performed for 30 seconds, the backlight is switched off again.- If you select "On", the backlight will remain on constantly.
P 13	Reduce backlighting 100 % |	20 % ( ) You can select 2 levels of brightness for the backlight.
P 14	Wireless module		After installation of a wireless module (with or without paired wireless remote control) in the appliance, menu item P 14 is enabled and "rc" appears on the programming unit display. You can pair one or more wireless remote controls; to do so, follow the pairing procedure on the appliance and the wireless remote control.Pressing "1" on the appliance for longer than 5 seconds starts the pairing process, which is shown on the programming unit of the appliance by a progress bar on the display and the operating LED flashing. Start the pairing process on the wireless remote control as described in the relevant operating instructions. After successful pairing, the operating LED on the appliance flashes briefly. An unsuccessful pairing attempt is automatically terminated after 30 seconds.Pressing "2" on the appliance for longer than 5 seconds unpairs all connected wireless remote controls. During unpairing, "rc0" appears on the display of the programming unit for 5 seconds, then "rc" again.

4.9.3 Deactivating the parameter menu

▶ Exit the menu item by pressing "i" and holding for more than 5 seconds. Alternatively: The system exits the menu item automatically 30 seconds after the setting has been completed.

OPERATION

Cleaning, care and maintenance

4.10 Recommended settings

Your instantaneous water heater offers maximum precision and maximum convenience in DHW provision. Should you nonetheless operate the appliance with a thermostatic valve, we recommend that you:

▶ Adjust the set temperature on the appliance to over 50 °C. Then set the required set temperature on the thermostatic valve.

Saving energy

The following recommended settings will result in the lowest energy consumption:

• 38 °C for hand washbasins, showers, bath
• 55 °C for kitchen sinks

Internal anti-scalding protection (qualified contractors)

If required, the qualified contractor can set a permanent temperature limit, for example in nurseries, hospitals, etc.

Recommended setting for operation with a thermostatic valve and water preheated by solar energy

▶ Set the temperature at the appliance to the maximum temperature.

Following an interruption to the water supply

Material losses

To ensure that the bare wire heating system is not damaged following an interruption to the water supply, the appliance must be recommissioned by taking the following steps.

▶ Disconnect the appliance from the power supply by removing the fuses/tripping the MCBs.
▶ Open the tap for one minute until the appliance and its upstream cold water inlet line are free of air.
▶ Switch on the power supply again.

5. Cleaning, care and maintenance

▶ Never use abrasive or corrosive cleaning agents. A damp cloth is sufficient for cleaning the appliance.
▶ Check the taps regularly. Limescale deposits at the tap outlets can be removed using commercially available descaling agents.

OPERATION

Troubleshooting

1. Troubleshooting

Problem Cause Remedy
The appliance will not start despite the DHW valve being fully open.	There is no power.	Check the fuses / MCBs in your fuse box / distribution board.
	The aerator in the tap or the shower head is scaled up or dirty.	Clean and/or descale the aerator or shower head.
The water supply has	been interrupted.	Vent the appliance and the cold water inlet line.
When hot water is being drawn off, cold water flows for a short period.	The air sensor is detecting air in the water. It briefly switches off the heating output.	The appliance restarts automatically after 1 minute.
The required temperature cannot be set.	The high limit safety cut-out and/or internal anti-scalding protection are enabled.	Deactivate the temperature limit. The internal anti-scalding protection can only be adjusted by qualified contractors.
The flow rate is too low.	ECO function is enabled.	Select a different ECO level or disable the ECO function.
No settings can be made on the programming unit.	The operating lock is enabled.	To deactivate the operating lock, press the "i" button for more than 12 seconds.

Note

Programming unit displays and selected settings are retained following a power failure.

If you cannot remedy the fault, contact your qualified contractor. To facilitate and speed up your enquiry, please provide the serial number from the type plate (000000-0000-000000).

Diagram illustrating a mechanical assembly or lifting process with labeled components and an inset detail view showing a component with text 'B1.00234605.0000'.

D0000053312

INSTALLATION

Safety

INSTALLATION

7. Safety

Only a qualified contractor should carry out installation, commissioning, maintenance and repair of the appliance.

7.1 General safety instructions

We guarantee trouble-free function and operational reliability only if original accessories and spare parts intended for the appliance are used.

Material losses

Observe the maximum inlet temperature. Higher temperatures may damage the appliance. You can limit the maximum inlet temperature by installing a central thermostatic valve (see chapter "Appliance description / Accessories").

WARNING Electrocution

This appliance contains capacitors which are discharged when disconnected from the power supply. The capacitor discharge voltage may briefly exceed 60 V DC.

7.2 Shower operation

CAUTION Burns

▶ When supplying a shower, set the internal anti-scalding protection to 55 °C or less; see chapter "Commissioning / Preparations".

CAUTION Burns

If operating with preheated water, e.g. if using a solar thermal system, observe the following information:

- The DHW temperature may exceed the set temperature or a set temperature limit.

- The dynamic anti-scalding protection between the appliance and a wireless remote control may not be effective.

▶ In such cases, limit the temperature with an upstream central thermostatic valve (e.g. ZTA 3/4).

7.3 Instructions, standards and regulations

Note

Observe all applicable national and regional regulations and instructions.

- The IP 24 / IP 25 protection rating can only be ensured with a correctly fitted cable grommet.

INSTALLATION

Appliance description

- The electrical resistivity of the water must not fall below that stated on the type plate. In a linked water network, take into consideration the lowest electrical resistivity of the water. Your water supply utility will advise you of the electrical resistivity or conductivity of the water in your area.

8. Appliance description

8.1 Standard delivery

The following are delivered with the appliance:

• Wall mounting bracket
• Installation template
• 2 twin nipples
• 3-way ball shut-off valve for cold water
• Tee for domestic hot water
• Flat gaskets
• Strainer
• Plastic profile washer
• Plastic connection pieces / installation aid
• Cover and back panel guides
• Jumper for internal anti-scalding protection

- Jumper for output changeover (only with DHE 18/21/24)

8.2 Accessories

Wireless remote control

- FFB 4 Set EU

Fittings

• MEKD mono lever kitchen pressure tap
• MEBD mono lever bath pressure tap

Water plugs G 12 A

If you use taps other than the recommended pressure taps on finished walls, please use the plugs.

Installation set for finished walls

• Solder fitting - copper pipe for soldered connection ∅ 12 mm
• Press fitting - copper pipe
• Press fitting – plastic pipe (suitable for Viega: Sanfix-Plus or Sanfix-Fosta)

Universal mounting frame

- Mounting frame with electrical connections

Pipe assembly for undersink appliances

You will need the undersink installation set if you make the water connections (G 38 A) at the top of the appliance.

INSTALLATION

Preparation

Pipe assembly for offset installation

Use this pipe assembly if you intend to offset the appliance by up to 90 mm downwards from the water connection.

Pipe assembly for replacing a gas water heater

You will need this pipe assembly set if the existing installation has gas water heater connections (cold water connection on the left-hand side, DHW connection on the right-hand side).

Pipe assembly for DHB water plug-in couplings

Use the water plug-in couplings if the existing installation contains water plug-in connections from a DHB water heater.

Load shedding relay (LR 1-A)

The load shedding relay for installation in the distribution board provides priority control for the instantaneous water heater when other appliances, such as electric storage heaters, are being operated simultaneously.

Central thermostatic valve (ZTA 3/4)

Use the thermostatic valve for central premixing, for example when operating an instantaneous water heater with preheated water. For use in shower operation, the valve must be set to a maximum of 55 °C.

9. Preparation

9.1 Installation site

Material losses

Install the appliance in a room that is free from the risk of frost.

▶ Always install the appliance vertically and near the draw-off point. For horizontal installation, see chapter "Installation alternatives / Horizontal installation of the appliance".

The appliance is suitable for undersink and oversink installation.

Undersink installation

D0000056242 1 2

Oversink installation

2 1 D0000057030

▶ Mount the appliance on the wall. The wall must have sufficient load bearing capacity.

9.2 Minimum clearances

≥60 ≥50≥50 ≥60 D0000060809

• Maintain the minimum clearances to ensure trouble-free operation of the appliance and facilitate maintenance work.

9.3 Water installation

▶ Flush the water line thoroughly.

Fittings

Use appropriate pressure taps. Open vented taps are not permissible.

Note

Never use the 3-way ball shut-off valve in the cold water inlet to reduce the flow rate. The 3-way ball shut-off valve is intended only to shut off the cold water inlet.

INSTALLATION

Installation

Permissible water line materials

• Cold water inlet line:
  Pipes made from galvanised steel, stainless steel, copper or plastic
• DHW outlet line:
  Pipes made from stainless steel, copper or plastic

Material losses

If plastic pipework systems are used, take into account the maximum inlet temperature and the maximum permissible pressure.

Flow rate

▶ Ensure that the flow rate for switching on the appliance is achieved.
▶ If the required flow rate is not achieved when the draw-off valve is fully open, increase the water line pressure.

10. Installation

Factory settings DHE 18/21/24 DHE 27
Internal anti-scalding protection °C 60 60
Connected load	kW	21	27
Adjustable connected load		x	-

Standard installation	DHE 18/21/24	DHE 27
Electrical connection from below on unfinished walls	x	x
Water connection on unfinished walls	x	x

For further installation options, see chapter "Alternative installation methods".

10.1 Standard installation

Opening the appliance

Diagram showing three stages of a mechanical device with labeled parts and directional arrows indicating motion or assembly.

INSTALLATION

Installation

▶ Open the appliance by holding the fascia at the side and puRitting the wall mounting bracket

ing forwards away from the appliance cover. Undo the screw.

Pivot open the appliance cover.

Mechanical assembly diagram showing two views of a device with internal components and directional arrows (no text or symbols)

▶ Remove the back panel by pressing the two locking tabs and pulling the lower back panel section forwards.

Preparing the power cable on unfinished walls, for connection from below

160 ≥30 1 D000053273

1 Cable entry installation aid

▶ Prepare the power cable.

Technical diagram of a mechanical component with mounting holes and internal features, displayed on grid paper (no text or symbols)

Mark out the holes for drilling using the installation template. If the appliance is to be installed on finished walls, also mark out the fixing hole in the lower section of the template.

▶ Drill the holes and secure the wall mounting bracket at 2 points using suitable fixing materials (screws and rawl plugs are not part of the standard delivery).

▶ Fit the wall mounting bracket.

Installing the twin nipples

Material losses

Carry out all water connection and installation work in accordance with regulations.

INSTALLATION

Installation

D000053319

▶ Seal and insert the twin nipples.

Making the water connection

2 1 24 5 Nm 3 2 5 4 D0000059695

1 DHW with tee
2 Gasket
3 Cold water with 3-way ball shut-off valve
4 Strainer
5 Plastic profile washer

- Secure the tee and 3-way ball shut-off valve, each with a flag gasket, to the twin nipples.

Material losses The strainer mu

The strainer must be fitted for the appliance to function.

▶ When replacing an appliance, check whether the strainer is installed.

Installing the appliance

Note

If you are installing the appliance with flexible pipe connections, also secure the back panel with a screw.

1 2 D0000053291

1 Cable entry installation aid
2 Cable grommet

Use the installation aid for easier wiring access through the cable grommet (see plastic parts set supplied).

▶ Remove the cable grommet from the back panel.

INSTALLATION

Installation

▶ Pull the cable grommet over the cable sheath of the power cable. For large cable cross-sections, enlarge the hole in the cable grommet if necessary.

Technical diagram showing mechanical assembly with labeled components and magnified views of a device

▶ Remove the transport protection plugs from the appliance pipe connections.
▶ Bend the power cable 45^ upwards.
▶ Route the power cable and cable grommet through the back panel from the rear.
▶ Install the appliance on the threaded studs of the wall mounting bracket.
▶ Press the back panel firmly into place, aligning it correctly.

• Lock the fixing toggle by turning it 90° clockwise.
  ▶ Pull the cable grommets into the back panel until both locking tabs engage.

19 3 Nm 24 5 Nm D0000056244

ENGLISH

▶ Fit the pipe connections with flat gaskets onto the water connections.

▶ Open the 3-way ball shut-off valve or the shut-off valve in the cold water inlet line.

INSTALLATION

Installation

Making the electrical connection

WARNING Electrocution

Carry out all electrical connection and installation work in accordance with relevant regulations.

WARNING Electrocution

The connection to the power supply must be in the form of a permanent connection in conjunction with the removable cable grommet. Ensure the appliance can be separated from the power supply by an isolator that disconnects all poles with at least 3 mm contact separation.

WARNING Electrocution

Ensure that the appliance is earthed.

Material losses

Observe the type plate. The specified rated voltage must match the power supply.

▶ Connect the power cable to the mains terminal.

Fitting the lower back panel section

Mechanical assembly diagram showing internal components and directional arrows (no text or labels)

D0000053275

1 Diffuser on lower back panel

▶ Fit the lower back panel section into the back panel. Check that both locking tabs are engaged.
▶ Align the mounted appliance by undoing the fixing toggle, aligning the power supply and back panel, and then re-tightening the fixing toggle. If the back panel does not sit flush against the wall, you can secure the appliance at the bottom with an additional screw.

Material losses

The cover plate of the lower back panel section must not bend when installed.

INSTALLATION

Commissioning

11. Commissioning

11.1 Preparation

Internal anti-scalding protection via jumper slot

T max 43 50 55 60

D0000089184

▶ Install the anti-scalding protection setting jumper in the required position (= temperature in °C) on the pin strip.

Jumper position Description

43 For example in nurseries, hospitals, etc.

50

55 Max. for shower operation

60 Factory setting

No jumper Limited to 43 °C

CAUTION Burns

If operating with preheated water, e.g. if using a solar thermal system, the internal anti-scalding protection and the temperature limit Tmax, which can be set by the user, may be exceeded.

In this case, limit the temperature with an upstream central thermostatic valve (e.g. ZTA 3/4).

INSTALLATION

Commissioning

Changing the connected load via jumper slot; only with DHE 18/21/24

If you select a connected load other than the 21 kW factory setting for appliances with selectable connected load, you will need to reposition the jumper.

Pmax 1 2 3 D000089187

▶ Install the jumper in the required position on the pin strip.

Jumper position Connected Load

1 18 kW
2 21 kW
3 24 kW
No jumper 18 kW

11.2 Initial start-up

on ≥ 60 s D000053277

▶ Open and close all connected draw-off valves several times, until all air has been purged from the pipework and the appliance.
Carry out a tightness check.

D0000053278

▶ Activate the safety switch by firmly pressing the reset button (the appliance is delivered with the safety switch disabled).

INSTALLATION

Commissioning

Diagram showing a server rack connected to a device with an inset close-up of its internal components (no text or symbols visible)

Connect the programming unit connecting cable to the PCB.

Tick the selected connected load and rated voltage on the appliance cover type plate (on both sides). Use a ballpoint pen to do this.
▶ Secure the appliance cover with the screw.
▶ Fit the fascia to the appliance cover.
▶ Remove the protective film from the user interface.

Note

For undersink installation, the appliance cover should be turned the other way up for easier operation; see chapter "Installation alternatives / Rotated appliance cover".

on

D0000053281

ENGLISH

D0000053280

▶ Hook the appliance cover at the top rear into the back panel.

Pivot the appliance cover downwards. Check that the appliance cover is securely seated both top and bottom.

▶ Switch on the power supply.

11.2.1 Appliance handover

Explain the appliance function to users and familiarise them with how it works.
▶ Make the user aware of potential dangers, especially the risk of scalding.
▶ Hand over the instructions.

INSTALLATION

Appliance shutdown

11.3 Recommissioning

Material losses

To ensure that the bare wire heating system is not damaged following an interruption to the water supply, the appliance must be recommissioned by taking the following steps.

▶ Disconnect the appliance from the power supply by removing the fuses/tripping the MCBs.
▶ Open the tap for at least one minute until the appliance and its upstream cold water inlet line are free of air.
▶ Switch on the power supply again.

12. Appliance shutdown

▶ Isolate all poles of the appliance from the power supply.
- Drain the appliance (see chapter "Maintenance / Draining the appliance").

13. Installation alternatives

Overview of installation alternatives

Electrical connection IP rating
On unfinished walls, connected from above IP 25
On unfinished walls, connected from below, short power cable	IP 25
Finished walls IP 24

Water connection IP rating

Finished walls IP 24
Other IP rating
Installation with offset tiles	IP 25
Rotated appliance cover	IP 25
Horizontal installation of the appliance	IP 24

WARNING Electrocution

Before any work on the appliance, disconnect all poles from the power supply.

INSTALLATION

Installation alternatives

13.1 Electrical connection from above on unfinished walls

140 ≥30 1 D000076507

1 Cable entry installation aid

▶ Prepare the power cable.

Diagram showing connections between electronic equipment blocks and a central device, with labeled components and wiring paths.

1 Cable routing

▶ Reposition the mains terminal from the bottom to the top. To do this, undo the fixing screw. Turn the mains terminal with connecting cables 180^ clockwise. Route the cable around the cable guide when doing so. Secure the mains terminal in place.
▶ Replace the cable grommets.
▶ Install the cable grommet from the top at the bottom.
▶ Pull the cable grommet over the cable sheath of the pow cable.
▶ Install the appliance on the threaded studs of the wall mounting bracket.
▶ Push the back panel firmly against the wall. Lock the fixing toggle by turning it 90° clockwise.
▶ Pull the cable grommets into the back panel until both locking tabs engage.
▶ Connect the power cable to the mains terminal.

WARNING Electrocution

The connecting wires must not protrude beyond the level of the mains terminal.

INSTALLATION

Installation alternatives

13.2 Electrical connection on unfinished walls from below with short power cable

D000060387

▶ Reposition the mains terminal further downwards. To do this undo the fixing screw. Secure the mains terminal in place.

13.3 Electrical connection on finished walls

Note

This type of connection changes the IP rating of the appliance.

▶ Change the type plate. Cross out "IP 25" and mark the box "IP 24". Use a ballpoint pen to do this.

30 A 1 D0000076506

1 Cable grommet

Electrical connection on finished walls Dimension A

Positioned in lower section of appliance 160

Positioned in upper section of appliance 110

▶ Prepare the power cable. Fit the cable grommet.

Material losses

If you break out the wrong knock-out in the back panel/appliance cover by mistake, you must use a new back panel/appliance cover.

▶ Cleanly cut and break out the required cable entries from the back panel and appliance cover (for the positions, see chapter "Specification / Dimensions and connections"). Deburr any sharp edges with a file.

Route the power cable through the cable grommet.
▶ Connect the power cable to the mains terminal.

INSTALLATION

Installation alternatives

13.4 Connecting a load shedding relay

Install a load shedding relay in the distribution board in conjunction with other electric appliances, e.g. electric storage heaters. The relay responds when the instantaneous water heater starts.

Material losses

Connect the phase that switches the load shedding relay to the indicated terminal of the mains terminal in the appliance (see chapter "Specification / Wiring diagram").

13.5 Water installation on finished walls

Note

This type of connection changes the IP rating of the appliance.

▶ Change the type plate. Cross out "IP 25" and mark the box "IP 24". Use a ballpoint pen to do this.

18 Nm 24 19 5 Nm D0000033104

▶ Fit water plugs with gaskets to seal the concealed connections. All taps obtained as accessories are supplied with plugs and gaskets in the standard delivery. For pressure taps other than those recommended by us, plugs and gaskets can be ordered as accessories.

▶ Fit a suitable pressure tap.
▶ Push the lower back panel section under the connection pipes of the tap and push it into the back panel.
- Secure the connection pipes to the tee and the 3-way ball shut-off valve.

Note

You can break off the pipe fitting tabs on the lower back panel section if required.

INSTALLATION

Installation alternatives

1 D0000056194

1 Tab

13.6 Water installation on finished walls with solder/press fittings

Note

This type of connection changes the IP rating of the appliance.

▶ Change the type plate. Cross out "IP 25" and mark the box "IP 24". Use a ballpoint pen to do this.

You can connect copper or plastic pipes with the accessories "solder fitting" or "press fitting".

With "solder fitting" with threaded fitting for 12 mm copper pipes, proceed as follows:

▶ Push the union nuts over the connection pipes.
▶ Solder the inserts to the copper pipes.
▶ Push the lower back panel section under the connection pipes of the tap and push it into the back panel.
- Secure the connection pipes to the tee and the 3-way ball shut-off valve.

Note

Observe the tap manufacturer's instructions.

13.7 Fitting appliance cover for water installation on finished walls

1 2 3 4 D000073170

1 Back panel guides
2 Screw
3 Cover guides with sealing lips on the pipe side
4 Pipe knock-out

▶ Cleanly saw and break out the pipe knock-outs in the appliance cover. If necessary, use a file.
▶ Click the cover guides into place in the knock-outs.

INSTALLATION

Installation alternatives

Only if using the "solder fitting" accessory and with precise adherence to all installation dimensions:

▶ Break the sealing lips out of the cover guides.
▶ Position the back panel guides on the pipes. Push them together. Then push the guides against the back panel as far they will go.
▶ Secure the lower back panel section with a screw.

Note

You can use the cover guides with sealing lips to compensate for a slight offset of the connection pipes and/or if using the "press fitting" accessory. In this case, the back panel guides are not fitted.

13.8 Lower back panel section installation with threaded fittings on finished walls

<2 1 2 3 D0000053286

1 Lower back panel section
2 Connection piece in the standard delivery
3 Screw

If using threaded fittings on finished walls, the lower back panel section can also be installed after fitting the taps. To do this, carry out the following steps:

▶ Cut open the lower back panel section.
▶ Fit the lower back panel section by bending it out at the sides and guiding it over the pipes.
▶ Insert the connection pieces into the lower back panel section from behind.

▶ Click the lower back panel section into place.
▶ Secure the lower back panel section with a screw.

INSTALLATION

Installation alternatives

13.9 Wall mounting bracket when replacing an appliance

An existing STIEBEL ELTRON wall mounting bracket may be used when replacing appliances (except the DHF instantaneous water heater), as long as the fixing screw is in the lower right position.

Replacing a DHF instantaneous water heater

Mechanical component diagram with mounting holes and a central shaft (no text or symbols)

▶ Reposition the fixing screw on the wall mounting bracket (the Maximum tile offset

fixing screw has a self-tapping thread).

▶ Rotate the wall mounting bracket 180^ and mount it on the wall (the DHF logo is then turned towards you).

13.10 Installation with offset tiles

2 ≤ 20 1 ≥ 110 26_02_02_1066_

1 Minimum contact area of the appliance
Maximum tile offset
▶ Adjust the wall clearance. Lock the back panel in place using the fixing toggle (turn 90° clockwise).

INSTALLATION

Installation alternatives

13.11 Rotated appliance cover

The appliance cover should be turned the other way up for undersink installation.

Diagram showing a door lock mechanism with directional arrows and a magnified inset view of the lock structure.

Diagram showing two connected devices with a cable, no text or symbols present

D0000073012

▶ Remove the programming unit from the appliance cover by pressing the locking hooks and removing the programming unit.
▶ Turn the appliance cover (not the appliance) the other way up and refit the programming unit. Push the programming unit home in parallel until all locking tabs engage. When engaging the locking tabs, apply counter pressure by pushing against the appliance cover from the inside.

WARNING Electrocution

All 4 locking tabs on the programming unit must click into place. The locking tabs must be complete and undamaged. If the programming unit is not inserted correctly, user protection against contact with live components cannot be ensured.

▶ Insert the connecting cable plug of the programming unit into the PCB (see chapter "Commissioning / Initial start-up").
▶ Hook the appliance cover in at the bottom. Pivot the appliance cover up to the back panel.
▶ Secure the appliance cover.
▶ Fit the cover onto the appliance cover.

13.12 Operation with preheated water

You can limit the maximum inlet temperature by installing a central thermostatic valve.

INSTALLATION

Installation alternatives

13.13 Horizontal installation of the appliance

Note

For the horizontal installation alternative, please note the following points:

• Installation is only permissible with direct wall mounting. The universal mounting frame cannot be used.
• The installation versions "Installation with offset tiles" and "Rotated appliance cover" are not permissible.
• This type of connection changes the IP rating of the appliance. Cross out "IP 25" on the type plate and mark the box "IP 24". Use a ballpoint pen to do this.

Horizontal installation

The appliance can also be mounted horizontally on the wall (turned 90° to the left, with the water connections on the right). The installation, water and electrical connections are described in chapters "Standard installation" and "Installation alternatives".

1 2 D000076919

The appliance cover must be provided with a condensate drain opening of min. ∅ 5.0 mm to max. ∅ 6.0 mm at the marked position.

Ø50 50 1 2 D000076914

1 Appliance cover with opening for condensate drain
2 Back panel with additional fixing screw

INSTALLATION

Service information

▶ Drill a hole from the outside through the dismantled appliance cover at the marked point. Alternatively, you can punch a hole in the appliance cover from the inside at the marked point. In this case, you must then enlarge the hole to the required diameter from the outside. Deburr any sharp edges with a file.
▶ Secure the appliance back panel with an additional screw.

Material losses

An appliance cover with an existing condensate drain opening must no longer be used for vertical installation of the appliance.

14. Service information

Overview of connections

1 2 3 4 5 6 7 D000073174

1 Motorised valve
2 Flow sensor
3 High limit safety cut-out, automatic reset
4 NTC sensor
5 Pin strips for connected load and anti-scalding protection
6 Programming unit plug-in position
7 Diagnostic traffic lights

INSTALLATION

Troubleshooting

Appliance cover retainer

Architectural floor plan showing room layouts and equipment layout (no text or labels)

15. Troubleshooting

WARNING Electrocution

To test the appliance, it must be connected to the power supply.

Note

When testing the appliance using the diagnostic traffic lights, water must be flowing.

Signals of the diagnostic traffic lights (LED)

●○○	Red Lights up in the event of a fault
○●○	Yellow	Illuminates in heating mode/flashes when output limit reached
○○●	Green Flashing: Appliance connected to power supply

INSTALLATION

Troubleshooting

Diagnostic traffic lights (draw-off mode)	Fault	Cause	Remedy
No LED illuminates Appliance does not heat upPCB faulty Replace the function module		One or more power supply phases are missing Check the fuses in the distribution board
Green flashing, yellow off, red off	No DHW	Appliance starting flow rate not reached; shower head/aerator scaled up	Descale/replace the shower head/aerator
		Appliance starting flow rate not reached; strainer in cold water inlet dirty	Clean strainer
		Flow meter not plugged in Check plug-in connection; correct if necessary
		Flow meter faulty or dirty Replace flow meter
PCB faulty Replace the function module
Green flashing, yellow on, red off	No display	Loose connecting cable between PCB and programming unit	Check plug-in connections; correct if necessary
		Faulty connecting cable between PCB and programming unit	Check connecting cable; replace if necessary
		Programming unit faulty	Replace programming unit
PCB faulty Replace the function module
Green flashing, yellow on, red off	No DHW; outlet temperature does not match set value	Tap faulty	Replace tap
		Outlet sensor faulty	Replace outlet sensor
		Heating system faulty	Replace the function module
PCB faulty Replace the function module
Green flashes, yellow flashes, red off	No DHW; outlet temperature does not match set value	Motorised valve faulty	Replace motorised valve
Green flashing, yellow off, red on	No DHW	One or more power supply phases are missing Check the fuses in the distribution board
		Air detection has responded	Continue draw-off for >1 min

INSTALLATION

Troubleshooting

15.1 Fault code display

If there is an appliance fault, the spanner flashes on the display.

▶ To call up the fault code display, press the "i" button for more

than 5 seconds.

Diagnostic traffic lights (draw-off mode)	Display shown	Fault	Cause	Remedy
Green flashing, yellow off, red on	Spanner flashes (fault code display E1 and spanner)	No DHW	Safety switch not activated during "Commissioning"	Activate the safety switch by firmly pressing the reset button
			Safety switch was triggered by high limit safety cut-out	Check high limit safety cut-out (plug-in connection, connecting cable); activate safety switch
			Safety switch responds again after high limit safety cut-out has been checked; high limit safety cut-out faulty	Replace high limit safety cut-out; activate safety switch and draw-off with maximum set value >1 min
Safety switch responds again; PCB			faulty	Replace the function module
Green flashing, yellow off, red on	Spanner flashes (fault code display E2 and spanner)	No DHW PCB faulty (lead break or short circuit in inlet sensor)		Replace the function module
Green flashing, yellow off, red on	Spanner flashes (fault code display E3 and spanner)	No DHW Short circuit in outlet sensor	Check outlet sensor;	replace if necessary

INSTALLATION

Maintenance

16. Maintenance

WARNING Electrocution

Before any work on the appliance, disconnect all poles from the power supply.

This appliance contains capacitors which are discharged when disconnected from the power supply. The capacitor discharge voltage may briefly exceed 60 V DC.

Draining the appliance

The appliance can be drained for maintenance work.

WARNING Burns

Hot water may escape when you drain the appliance.

▶ Close the 3-way ball shut-off valve or the shut-off valve in the cold water inlet line.
▶ Open all draw-off valves.
▶ Undo the pipe connections from the appliance.
▶ Store the dismantled appliance free from the risk of frost, as water residues remaining inside the appliance can freeze and cause damage.

Clean strainer

If the strainer in the threaded cold water fitting is dirty, clean it. Close the 3-way ball shut-off valve or the shut-off valve in the cold water inlet line before removing, cleaning and refitting the strainer.

INSTALLATION

Specification

17. Specification

17.1 Dimensions and connections

225 140 466 414 368 b02 30 38 100 C01c06 105≤20 35 116 D0000073253

DHE
b02	Entry for electrical cables | Unfinished walls
c01	Cold water inlet Male thread	G 1/2 A
c06	DHW outlet	Male thread	G 1/2 A

Alternative connection options

b03 330 20 b04 b02 30 b04 325 69 35 69 165 b04 b04 D0000053293

DHE
b02	Entry for electrical cables I Unfinished walls
b03	Entry for electrical cables II Unfinished walls
b04	Entry electrical cables III Finished walls

INSTALLATION

Specification

17.2 Wiring diagram

3/PE \~ 380-415 V

2 1 L1 L2 L3 4 3 D000053424

1 Power PCB with integral safety switch
2 Bare wire heating system
3 High limit safety cut-out
4 Mains terminal

Priority control with LR 1-A

2 1 L L L 12 85_02_02_0003_

1 Control cable to the contactor of the second appliance (e.g. electric storage heater)
2 Control contact drops out when switching the instantaneous water heater on.

INSTALLATION

Specification

17.3 DHW output

The DHW output is subject to the connected power supply, the appliance's connected load and the cold water inlet temperature. The rated voltage and rated output can be found on the type plate.

Connected load in kW 38 °C DHW output in L/min.

Rated voltage Cold water inlet temperature

380 V 400 V 415 V 5 °C 10 °C 15 °C 20 °C

DHE 18/21/24
16.2		7.0	8.3	10.1	12.9
19.0		8.2	9.7	11.8	15.1
21.7		9.4	11.1	13.5	17.2
	18.0	7.8	9.2	11.2	14.3
	21.0	9.1	10.7	13.0	16.7
	24.0	10.4	12.2	14.9	19.0
		19.4	8.4	9.9	12.0
		22.6	9.8	11.5	14.0
		25.8	11.2	13.2	16.0
DHE 27
24.4		10.6	12.4	15.2	19.4
	27.0	11.7	13.8	16.8	21.4

Connected load in kW 50 °C DHW output in L/min.

Rated voltage Cold water inlet temperature

380 V 400 V 415 V 5 °C 10 °C 15 °C 20 °C

DHE 18/21/24
16.2		5.1	5.8	6.6	7.7
19.0		6.0	6.8	7.8	9.0
21.7		6.9	7.8	8.9	10.3
	18.0	5.7	6.4	7.3	8.6
	21.0	6.7	7.5	8.6	10.0
	24.0	7.6	8.6	9.8	11.4
		19.4	6.2	6.9	7.9
		22.6	7.2	8.1	9.2
		25.8	8.2	9.2	10.5
DHE 27
24.4		7.7	8.7	10.0	11.6
	27.0	8.6	9.6	11.0	12.9

17.4 Application areas / conversion table

Electrical resistivity and electrical conductivity

Standard specification at 15 °C			20 °C			25 °C
Resistivity ≥	Conductivity ≤		Resistivity ≥	Conductivity ≤		Resistivity ≥	Conductivity ≤
	mS/m	μS/cm		mS/m	μS/cm		mS/m	μS/cm
900	111	1111	800	125	1250	735	136	1361

INSTALLATION

Specification

17.5 Pressure drop

Fittings

Tap pressure drop at a flow rate of 10 L/min
Mono lever mixer tap, approx. MPa 0.04 - 0.08
Thermostatic valve, approx. MPa 0.03 - 0.05
Shower head, approx. MPa 0.03 - 0.15

Sizing the pipework

When calculating the size of the pipework, an appliance pressure drop of 0.1 MPa is recommended.

17.6 Fault conditions

In the event of a fault, loads up to 80 °C at a pressure of 1.0 MPa can occur briefly in the installation.

17.7 Energy consumption data

Product datasheet: Conventional water heaters to regulation (EU) no. 812/2013 | 814/2013

DHE 18/21/24 DHE 27
		202656	202657
Manufacturer		STIEBEL ELTRON	STIEBEL ELTRON
Load profile		S	S
Energy efficiency class		A	A
Energy conversion efficiency	%	39	39
Annual power consumption	kWh	476	475
Default temperature setting	°C	60	60
Sound power level	dB(A)	15	15
Special information on measuring efficiency		Measured at ECO level with highest flow rate, maximum output and maximum set value.	Measured at ECO level with highest flow rate and maximum set value
Daily power consumption	kWh	2,184	2,177

INSTALLATION

Specification

17.8 Data table

DHE 18/21/24 DHE 27
202656 202657
Electrical data
Rated voltage	V	380	400	415	380	400
Rated output	kW	16.2/19/21.7	18/21/24	19.4/22.6/25.8	24.4	27
Rated current	A	27.6/29.5/33.3	29/31/35	30.1/32.2/36.3	37.1	39
Fuse protection	A	32/32/35	32/32/35	32/32/40	40	40
Frequency	Hz	50/60	50/60	50/-	50/-	50/-
Phases				3/PE		3/PE
Resistivity ρ15 ≥	Ω cm			900		900
Conductivity σ15 ≤	μS/cm			1111		1111
Max. mains impedance at 50 Hz	Ω	0.248	0.236	0.227	0.221	0.210
Connections
Water connection				G 1/2 A		G 1/2 A
Application limits
Max. permissible pressure	MPa			1		1
Max. inlet temperature for reheating	°C			55		55
Values
Max. inlet temperature (e.g. pasteurisation)	°C			70		70
On	l/min			>2.5		>2.5
Flow rate at 28 K	l/min		9.2/10.7/12.3 at 400 V		13.8 at 400 V
Flow rate at 50 K	l/min		5.2/6.0/6.9 at 400 V		7.7 at 400 V
Pressure drop for flow rate at 50 K (without flow limiter)	MPa		0.06/0.08/0.1		0.13
Hydraulic data
Nominal capacity	l			0.4		0.4

INSTALLATION

Specification

DHE 18/21/24 DHE 27
Versions
Adjustable connected load X -
Temperature settings °C Off, 20-60 Off, 20-60
Protection class	1	1
Insulating block		Plastic	Plastic
Heating system heat generator		Bare wire	Bare wire
Cover and back panel		Plastic	Plastic
Colour		White	White
IP rating		IP 25	IP 25
Dimensions
Height	mm	466	466
Width	mm	225	225
Depth	mm	116	116
Weights
Weight	kg	3.1	3.1

Note

The appliance conforms to IEC 61000-3-12.

GUARANTEE | ENVIRONMENT AND RECYCLING

Guarantee

The guarantee conditions of our German companies do not apply to appliances acquired outside of Germany. In countries where our subsidiaries sell our products a guarantee can only be issued by those subsidiaries. Such guarantee is only granted if the subsidiary has issued its own terms of guarantee. No other guarantee will be granted.

We shall not provide any guarantee for appliances acquired in countries where we have no subsidiary to sell our products. This will not affect warranties issued by any importers.

Environment and recycling

We would ask you to help protect the environment. After use, dispose of the various materials in accordance with national regulations.

TABLE DES MATIÈRES

REMARQUES PARTICULIÈRES

UTILISATION

Diagram illustrating a mechanical assembly or lifting process with labeled components and an inset detail view showing a component with dimension annotation.

D0000053312

INSTALLATION

Sécurité

INSTALLATION

7. Sécurité

9.3 Installation hydraulique

Three sequential diagrams showing a cylindrical object being inserted into a base, with arrows indicating the process (no text or symbols present)

D0000053271

INSTALLATION

Montage

Mechanical assembly diagram showing two views of a device with internal components and directional arrows (no text or symbols)

Technical diagram of a mechanical component with mounting holes and directional arrows on a grid background (no text or symbols)

Technical diagram of a mechanical assembly with labeled components and magnified views showing internal parts.

Mechanical assembly diagram showing a component with directional arrows, no visible text or symbols

D0000053275

Technical diagram showing a refrigerator unit and its close-up of internal components (no text or symbols visible)

Three-step diagram showing a cylindrical device being inserted into a base, with an arrow indicating the process (no text or symbols present)

Diagram showing connections between electronic equipment blocks with labeled components and a magnified inset highlighting a central device.

1 Câblage

Mechanical component diagram with mounting holes and a central shaft (no text or symbols)

Diagram showing a door lock mechanism with directional arrows and a magnified inset view of the lock structure.

Diagram showing two connected devices with a cable, no text or symbols present

D0000073012

Architectural floor plan showing room layout and equipment placement (no text or labels)

2 1 L1' L2' L3' 4 3 L1 L D0000053424

2 1 L L L I2 85_02_02_0003_

375°C 125- 4 3 5 6 7 ① i ② 2 + 1 Made in January

D0000091079

Diagram illustrating a mechanical or fluid system with labeled components and directional arrows, including an inset magnified view.

D0000053312

INSTALLATIE

Veiligheid

INSTALLATIE

7. Veiligheid

Diagram showing three stages of a mechanical device with labeled parts and directional arrows indicating motion or assembly.

INSTALLATIE

Montage

Mechanical assembly diagram showing two views of a device with internal components and directional arrows (no text or symbols)

Technical diagram of a mechanical component with mounting holes and mounting points, displayed on grid background (no text or symbols)

▶ Monteer de wandbevestiging.

Technical diagram showing mechanical assembly with labeled components and magnified views of parts

Mechanical assembly diagram showing internal components and directional arrows (no text or labels)

D0000053275

Diagram showing a refrigerator with a magnified inset of a kitchen appliance (no text or symbols present)

▶ Steek de verbindingskabel van de bedieningseenheid op de elektronica.

Info

Three-step diagram showing a device with a cylindrical component being inserted into a container, then moving to a base (no text or symbols present)

Mechanical component diagram with mounting holes and a central pin (no text or symbols)

Diagram showing a door lock mechanism with directional arrows and a magnified inset view of the lock structure.

Diagram showing two connected devices with a cable, no text or symbols present

D0000073012

Architectural floor plan showing room layout and furniture placement (no text or labels)

15. Storingen verhelpen

WAARSCHUWING verbranding

Diagram illustrating a mechanical assembly process with labeled parts and an inset magnified view showing a component detail.

DOOOO5312

Three sequential diagrams showing a cylindrical device with a base, with arrows indicating motion and a small object nearby (no text or symbols)

Mechanical assembly diagrams showing two views of a valve mechanism (no text or labels)

Technical diagram of a mechanical component with mounting holes and internal features, displayed on grid paper (no text or symbols)

Technical diagram showing a mechanical assembly with three circular insets highlighting different components, including a gear and tool.

Technical diagram of a mechanical assembly with directional arrows, no visible text or symbols

D0000053275

Diagram showing a magnified view of a mechanical component inserted into a bracket, with no visible text or symbols.

D0000053278

Diagram showing a refrigerator with a close-up view of its interior components (no text or symbols present)

D0000073198

Three sequential diagrams showing a mechanical device with a cylindrical component, connected to a base with an arrow indicating motion (no text or symbols)

082500000

INSTALACE

Uvedení mimo provoz

Diagram showing two identical electrical or mechanical components with wiring and connectors, no text or symbols present.

D0000060387

Mechanical component with mounting holes and a central switch (no text or symbols visible)

Technical diagram showing electrical connection setup with labeled components and a magnified inset view of a device panel.

Architectural floor plan showing room layout and furniture placement (no text or labels)

Diagram illustrating a mechanical or electrical setup with labeled components and directional arrows, including a magnified inset showing a component detail.

D0000053312

INSTALACJA

Bezpieczeństwo

INSTALACJA

7. Bezpieczeństwo

Diagram showing three stages of a device with labeled parts and directional arrows indicating motion or assembly.

Mechanical assembly diagrams showing two views of a mechanical component with no visible text or symbols

Technical diagram of a mechanical component with mounting holes and internal features, displayed on grid paper (no text or symbols)

Technical diagram showing a mechanical assembly with three circular insets highlighting different components, including a worker in a workshop.

Diagram showing a refrigerator with a close-up of its interior air conditioner unit (no text or symbols visible)

D0000073198

Three sequential diagrams showing a mechanical setup with a cylindrical component, a spring, and a base with an arrow indicating motion (no text or symbols)

D0000053280

Technical cross-section diagram of a mechanical component with labeled part 1 (no readable text or symbols beyond label)

1 łącznik

Technical diagram of a mechanical assembly with labeled components and dimensional annotations

Mechanical component diagram with mounting holes and a central pin (no text or symbols)

Diagram showing a door lock mechanism with directional arrows and a magnified inset view of the lock structure.

Diagram showing two connected devices with a cable, no text or symbols present

D0000073012

Architectural floor plan showing room layout and equipment placement (no text or labels)

INSTALACJA

Usuwanie usterek

2 1 L L L 12 85_02_02_0003_

Floor plan diagram of a residential apartment with furniture layout (no text or labels)

Diagram showing a door mechanism with directional arrows and a magnified inset highlighting the interior detail.

Diagram showing two connected devices with a labeled connection point, likely illustrating a measurement or control system.

D0000073012

2 ≤20 1 ≥110

26 02 02 1066

Mechanical component diagram with mounting holes and a central switch (no text or symbols)

Cross-sectional diagram of a mechanical assembly with no visible text or symbols

D0000056194

1 لسان

4.33.13.14.15.16.17.18.19.20.21.22.23.24.25.26.27.28.29.30.31.32.33.34.35.36.37.38.39.40.41.42.43.44.45.46.47.48.49.50.51.52.53.54.55.56.57.58.59.60.61.62.63.64.65.66.67.68.69.70.71.72.73.74.75.76.77.78.79.80.81.82.83.84.85.86.87.88.89.90.91.92.93.94.95.96.97.98.99.100

Diagram showing two connected devices with connectors and wiring, indicating a process or system change.

D0000060387

Diagram showing a refrigerator with a magnified inset of a kitchen appliance (no text or symbols present)

Three sequential diagrams showing a device with a cylindrical component being inserted, then moving to a base (no text or symbols present)

The image contains a graphical symbol (a lightning bolt inside a triangle) and no textual content. Therefore, the correct OCR output is an empty string.

The image contains a graphical symbol (a lightning bolt) inside a triangle, which is not standard alphanumeric text. According to the instructions, non-text figures/diagrams are to be ignored. Therefore, no OCR output is generated.

The image contains a graphical symbol (a lightning bolt inside a triangle) and no textual content. Therefore, the correct OCR output is an empty string.

Diagram showing mechanical assembly with labeled parts 1 and 2, including a tool and component layout

291

Technical drawing of a mechanical component with mounting holes and mounting features, set on a grid background (no text or symbols)

Mechanical assembly diagrams showing two views of a mechanical component with no visible text or symbols

Three sequential diagrams showing a cylindrical object being inserted into a base, with no text or symbols present.

التدفق الحجمي

الجهاز.

السحب

Diagram of a bathroom sink with labeled components and directional arrows indicating flow or movement.

D0000056242

294 Salmon Street | Port Melbourne

VIC 3207

Tel. [phone] | Fax [phone]

[e-mail]

www.stiebel-eltron.com.au

Austria

STIEBEL ELTRON Ges.m.b.H.

Plant C3. XEDA International Industry City

Xiqing Economic Development Area

300085 Tianjin

Tel. [phone] | Fax [phone]

[e-mail]

www.stiebeleltron.cn

Czech Republic

STIEBEL ELTRON spol. s r.o.

Urzhumskaya street 4,

building 2 | 129343 Moscow

Tel. [phone] | Fax [phone]

[e-mail]

www.stiebel-eltron.ru

Slovakia

STIEBEL ELTRON Slovakia, s.r.o.

Hlavná 1 | 058 01 Poprad

Tel. [phone] | Fax [phone]

[e-mail]

www.stiebel-eltron.sk

Switzerland

STIEBEL ELTRON AG

Industrie West

Gass 8 | 5242 Lupfig

Tel. [phone] | Fax [phone]

[e-mail]

www.stiebel-eltron.ch

Thailand

STIEBEL ELTRON Asia Ltd

469 Moo 2 Tambol Klong-lik

Amphur Bangpa-In | 13160 Ayutthaya

Tel. [phone] | Fax [phone]

[e-mail]

www.stiebeleltronasia.com

United Kingdom and Ireland

STIEBEL ELTRON UK Ltd

Unit 12 Stadium Court

Stadium Road | CH62 3RP Bromborough

Tel. [phone] | Fax [phone]

[e-mail]

www.stiebel-eltron.co.uk

United States of America

STIEBEL ELTRON, Inc.

17 West Street | 01088 West Hatfield MA

Tel. [phone] | Fax [phone]

[e-mail]

www.stiebel-eltron-usa.com

STIEBEL ELTRON

Irrtum und technische Änderungen vorbehalten! | Subject to errors and technical changes! | Sous réserve d'erreurs et de modifications techniques! | Onder voorbehoud van vergissingen en technische wijzigingen! | Salvo error o modific aciontechnica! | Excepto erro ou alteraçatécnica | Zastrzezone zmianytechniczne i ewentualne będyl | Mylya technikézmýjs ou vyhrazeny! | Amuszak iváltoztatások éstévedésej koäfte nntartjuk! | Osttvsüthie ошибokne garantiuret. Возможны технические изменения. | Chyby a techniké zmeny sú vyhradeně! Stand 9535