Pegasus - Central heating boiler FERROLI - Free user manual and instructions

USER MANUAL Pegasus FERROLI

1. GENERAL INSTRUCTIONS• Carefully read the instructions contained in this instruction booklet.• After boiler installation, inform the user regarding its operation and give him this manual, which is an integraland essential part of the product and must be kept with care for future reference.• Installation and maintenance must be carried out by professionally qualified personnel, according to currentregulations and the manufacturer's instructions. Do not carry out any operation on the sealed control parts.• Incorrect installation or inadequate maintenance can result in damage or injury. The Manufacturer declinesany liability for damage due to errors in installation and use or failure to follow the instructions.• Before carrying out any cleaning or maintenance operation, disconnect the unit from the power supply usingthe system switch and/or the special cut-off devices.• In case of a fault and/or poor operation, deactivate the unit and do not attempt to repair it or directly intervene.Contact professionally qualified personnel. Repair/replacement of the products must only be carried out byprofessionally qualified using original spare parts. Failure to comply with the above could affect the safety ofthe unit.• This unit must only be used for its intended purpose. Any other use is considered improper and thereforedangerous.• The packing materials are potentially hazardous and must not be left within the reach of children.• The images given in this manual are a simplified representation of the product. In this representation theremay be slight and insignificant differences with respect to the product supplied.2. INSTALLATION2.1 IntroductionDear Customer, Thank you for choosing PEGASUS 67 ÷ 107 2S, a floor-standing boilerFERROLI featur- ing advanced design, cutting-edge technology , high reliability and quality construction.Please read this manual carefully and keep it for future reference. PEGASUS 67 ÷ 107 2S is a high-efficiency heat generator with low NOx emissions for central heating, running on natural gas or liquefied gas, equipped with an advancedelectronic control system.The boiler shell consists of cast-iron elements whose particular shape guarantees highexchange efficiency in all operating conditions, and an open-flue burner equipped withelectronic ignition and ionisation flame control.The boiler also has an automatic air vent valve, a 2-stage control thermostat and safetythermostat.Thanks to the electronic ignition and flame control system, boiler operation is for the mostpart automatic.The user only has to set the system temperature by means of the control thermostat.2.2 Control panelTo access the control panel, lift the front door.fig. 1 - Control panel Key 1 Arrangement for thermostatic controller2 Boiler thermomanometer3 Manual-reset safety thermostat cover4 Manual-reset fume thermostat cover5 Cap6 Flame controller reset button with shutdown light7 2-stage boiler control thermostat8 0 - 1 - TEST switch2.3 Lighting and turning offLighting• Open the gas cock ahead of the boiler.• Turn on or insert the switch or plug ahead of the boiler.• Turn the boiler switch "8" to 1 (fig. 1).• Turn knob "7" to the selected temperature and any room thermostat to the requiredtemperature value. The burner will light and the boiler starts working automatically,controlled by its adjustment and safety devices.• If the boiler is equipped with an electronic thermostatic controller fitted in position1fig. 1 of , the user must also take into account the manufacturer's instructions.

If the burners do not light and the shutdown button-indicator "6" comes on af- ter correctly carrying out the lighting procedures, wait about 15secondsand then press the above-mentioned button. The flame controller () reset in thisway will then repeat the ignition cycle. If the burners do not light even after sev-eral attempts, consult the faults section. In case of a power failure while the boiler is working, the burners will go out andrelight automatically when the power is restored.Turning offClose the gas cock ahead of the boiler, turn knob "8" to 0 and disconnect the power. To avoid damage caused by freezing during long shutdowns in winter, it is ad-visable to drain all water from the boiler and system; or add a suitable antifreezeto the heating system.The boiler switch 8 has 3 positions “0-1-TEST”; the first two have the on-offfunction, the third (unstable) must only be used for service and maintenancepurposes.2.4 AdjustmentsSystem temperature adjustmentTurn the knob 7 of fig. 1 clockwise to increase the heating water temperature, or anti-clockwise to decrease it. The temperature can be varied from a minimum of 30°C to amaximum of 90°C. However, it is advisable not to operate the boiler below 45°C.Room temperature adjustment (with optional room thermostat)Using the room thermostat, set the required temperature in the rooms. By command ofthe room thermostat, the boiler lights and brings the system water to the temperature setby boiler adjustment thermostat 7 of fig. 1. The generator turns off when the requiredtemperature in the rooms is reached.If the room thermostat is not installed the boiler will keep the system at the temperatureset by the boiler control thermostat.Water system pressure adjustmentThe filling pressure with system cold, read on the boiler water gauge detail 2 of fig. 1,must be approx. 1.0 bar. If, during operation, the system pressure falls (due to the evap-oration of gases dissolved in the water) to values below the minimum described above,the user must bring it to the initial value by operating the filling cock. At the end of theoperation always close the filling cock.2.5 FaultsListed below are faults that can be caused by simple, user-solvable problems. Before calling the after-sales service, check that the problem is not due to nogas or electricity.3. INSTALLATION3.1 General Instructions This unit must only be used for its intended purpose.This unit is designed to heat water to a temperature below boiling point at at-mospheric pressure and must be connected to a heating system and/or a watersupply system for domestic use, compatible with its performance, characteris-tics and its heating capacity. Any other use is considered improper.THE BOILER MUST ONLY BE INSTALLED BY QUALIFIED PERSONNEL, IN AC-CORDANCE WITH ALL THE INSTRUCTIONS GIVEN IN THIS TECHNICAL MANUAL,THE PROVISIONS OF CURRENT LAW, ANY LOCAL REGULATIONS AND THERULES OF PROPER WORKMANSHIP.The Manufacturer declines any liability for damage or injury caused by incorrect installa-tion.3.2 Place of installationThis unit is an “open chamber” type and can only be installed and operated in perma-nently ventilated rooms. An insufficient flow of combustion air to the boiler will affect itsnormal operation and fume evacuation. Also, the fumes forming in these conditions (ox-ides) are extremely harmful to the health if dispersed in the domestic environment.Therefore the place of installation must be free of dust, flammable materials or objectsor corrosive gases. The room must be dry and not subject to freezing.When positioning the boiler, leave sufficient space around it for normal maintenance ac-tivities. Symbol Faults CureBoiler shutdown by the flame controllerMake sure the gas cocks ahead of the boiler and on the meter are open.Press the lit pushbutton-indicator.In case of repeated shutdowns, contact the nearest service centre.Boiler shutdown due to insufficient sys-tem pressure (only if a pressure switch is installed in the system)Fill the system to 1-1.5 bar cold by means of the sys-tem filling cock.Close the cock after use.Boiler shutdown due to insufficient evac-uation of fumesUnscrew the fume thermostat cover and press the button below.In case of repeated boiler shutdowns, contact the nearest service centre.Boiler shutdown due to water overtem-peratureUnscrew the safety thermostat cover and press the button below.In case of repeated boiler shutdowns, contact the nearest service centre.cod. 3540S433 - Rev. 02 - 04/2018PEGASUS 67 ÷ 107 2S

3.3 Plumbing connections

Important The heating capacity of the unit must be previously established by calculating the build- ing's heat requirement according to the current regulations. To ensure proper operation and long boiler life, the plumbing system must be adequately sized and complete with all the necessary accessories. If the delivery and return pipes follow a path where air pockets can form in certain places, it is advisable to install vent valves at these points. Also, install a discharge device at the lowest point in the system to allow its complete emptying. If the boiler is installed at a lower level than the system, it is advisable to provide a flow- stop valve to prevent the natural circulation of water in the system. The temperature drop between the delivery manifold and the return to the boiler should not exceed 20°C.

Do not use the water system pipes to earth electrical appliances. Before installation, carefully wash all the pipes of the system to remove any residuals or impurities that could affect proper operation of the unit. Carry out the relevant connections as indicated in fig. 13. It is advisable to install shutoff valves between the boiler and heating system, allowing the boiler to be isolated from the system if necessary.

Make the boiler connection in such a way that its internal pipes are free of stress. Water system characteristics In the presence of water harder than 25° Fr, it is advisable to use suitably treated water, in order to avoid possible scaling in the boiler caused by hard water, or corrosion pro- duced by aggressive water. Due to its low thermal conductivity, scaling even just a few mm thick causes significant overheating of the boiler walls with consequent serious prob- lems. Water treatment is indispensable in case of very large systems (containing large amounts of water) or with frequent introduction of replenishing water in the system. If par- tial or total emptying of the system becomes necessary in these cases, it is advisable to refill with treated water. Filling boiler and system The filling pressure with system cold system must be approx. 1 bar. If, during operation, the system pressure falls (due to the evaporation of gases dissolved in the water) to val- ues below the minimum described above, the user must bring it to the initial value. For correct operation of the boiler, when hot, its pressure must be approx. 1.5-2 bar.

Before carrying out the connection, make sure the unit is arranged for using the type of fuel available and carefully clean all the pipes of the gas system to re- move any residues that could affect proper boiler operation. The gas must be connected to the relevant connection (see fig. 13) in conformity with current standards, with a rigid metal pipe or with a continuous surface flexible s/steel tube, installing a gas cock between the system and boiler. Make sure all the gas connec- tions are tight. The capacity of the gas meter must be sufficient for the simultaneous use of all equip- ment connected to it. The diameter of the gas pipe leaving the boiler does not determine the diameter of the pipe between the unit and the meter; it must be chosen according to its length and pressure losses, in conformity with the current regulations.

Do not use the gas pipes to earth electrical appliances.

3.5 Electrical connections

Connection to the power supply The boiler must be connected to a single-phase, 230 Volt-50 Hz electric line.

The unit's electrical safety is guaranteed only when it is correctly connected to an efficient earthing system in conformity with the current safety regulations. Have the efficiency and suitability of the earthing system checked by profes- sionally qualified personnel; the Manufacturer declines any liability for damage caused by failure to earth the system. Also make sure the electrical system is adequate for the maximum power absorbed by the unit, as specified on the boil- er dataplate, in particular ensuring that the section of the system's cables is suitable for the input. The boiler is prewired and supplied with a connector located inside the control panel, ar- ranged for connection to an electronic thermostatic controller (see wiring diagrams in sec. 5.5). It is also equipped with a three-core cable for connection to the electric line. The connections to the power supply must be made with a permanent connection and equipped with a double-pole switch with contact gap of at least 3 mm, interposing fuses of max. 3A between the boiler and line. It is important to respect the polarities (LINE: brown wire / NEUTRAL: blue wire / EARTH : yellow/green wire) when making the con- nections to the electric line. Accessing the electrical terminal block and components inside the control panel To access the electrical components inside the control panel, follow the sequence in fig. 2. The layout of the terminals for the various connections is given in the wiring dia- grams in the technical data section. fig. 2 - Accessing the terminal block Key

Undo the 2 self-tapping screws securing the boiler cover.

Lift by pressing upwards and remove the cover held to the sides of the boiler by pins.

Undo and remove the two screws and the two plates holding the control panel.

Turn the control panel forwards. Any additional sensitive elements of the system's control and safety devices, tempera- ture probe, pressure switch, thermostat bulb, etc., must be located on the delivery pipe within 40 cm of the boiler casing rear wall (see fig. 3). Key

3.6 Connection to the flue

The flue connection pipe diameter must not be less than that of the connection on the anti-backflow device. Starting from the anti-backflow device it must have a vertical sec- tion at least 50 cm long. Comply with the current regulations regarding installation and sizes of the flues and connection pipe. The diameters of the anti-backflow device collars are given in table 1.

All adjustment and conversion operations must be carried out by Qualified Personnel. The manufacturer declines any liability for damage or injury caused by unqualified and unauthor- ised people tampering with the unit. Burner gas pressure adjustment The boilers PEGASUS 67 ÷ 107 2S are arranged to run on natural or liquefied gas. The pressure setting and test are performed in the factory. However, at first lighting, as there may be supply pressure variations, check and if necessary ad- just the pressure at the nozzles, respecting the values given in the technical data table in sec. 5.3

Pressure adjustment operations must be carried out with the boiler working, using the pressure regulator on the 2-stage gas valves (see fig. 4

Preliminary operations:

1. Light the boiler and turn the control thermostat knob to minimum.

2. Connect a pressure gauge to the pressure point on the gas manifold pipe of the burner as-

sembly (see part 14 of fig. 14

3. Remove the protection cap of the pressure regulator 4 of

Minimum power (1st stage) adjustment

1. Turn the control thermostat knob slowly clockwise to the 1st click; the gas valve will thus be

supplied only on connections A and B (see fig. 4

2. Turn the screw 6 of

The diameter of the connecting pipe to the flue must not be less than that of the connec- tion on the anti-backflow device. Starting from the anti-backflow device it must have a vertical section at least 50 cm long. The current regulations must be respected regarding the dimensioning and installation of the flues and connection pipe. The boiler is a B11BS type equipped with a safety device (fume thermostat) that stops the supply of gas and shuts down the unit in case of poor draught or disturbance in the fume exhaust. Unit shutdown is indicated on the display with the code F04 (ref. cap. 3.4). Restarting of the unit occurs automatically 20 minutes after the end of the fault that caused the problem. In case of repeated intervention of the device, contact qualified per- sonnel to check the flue and chimney and eliminate the fume evacuation fault.

This safety device must never be tampered with or deactivated. Any operation on the device, or its replacement, must only be carried out by qualified person- nel using the manufacturer's original replacement parts. A functional test must be carried out after any operation on the device. cod. 3540S433 - Rev. 02 - 04/2018PEGASUS 67 ÷ 107 2S

Maximum power (2nd stage) adjustment1. Turn the control thermostat knob to maximum; the gas valve will now be supplied only on con-nections A, B and C (see fig. 4 2. Turn the screw 5 of fig. 4, checking that the pressure matches the values given in the tech-nical data table in sec. 5.3 The adjustment operations must be performed uniformly on the pressure regulators of all thevalves. The gas pressures measured at the burner gas manifold must be read at least 30 sec-onds after making the adjustments, i.e. when the flame has stabilised.On completing the adjustment operations, turn the burner on and off 2 - 3 times with the controlthermostat and check that the pressure values are those just set; otherwise, it is necessary tomake another adjustment to bring the pressures to the correct values.Gas conversionThe unit can work with Natural gas (G20-G25) or liquefied gas (G30-G31) and is factory-set for use with one of the two gases, as clearly shown on the packing and dataplate.Whenever the unit has to be used with a different gas, a conversion kit will be required,proceeding as follows.From natural to liquefied gas1. Replace the nozzles at the main burner and pilot burner, fitting the nozzles specifiedin the technical data table in sec. 5.3.2. Remove the small cap 3 (fig. 4) from the gas valve, screw the ignition "STEP" regu-lator 2 (contained in the conversion kit) onto the valve and refit the cap 3 on the reg-ulator.3. Adjust the burner gas pressures for minimum and maximum power as described inthe previous section, setting the values given in the technical data table of sectionsec. 5.3.4. Operations 2 and 3 must be performed on all the valves.5. Apply the sticker contained in the conversion kit, near the dataplate as proof of theconversion.From liquefied to natural gasCarry out the same operations described above, making sure to remove the ignition "STEP" regulator 2 of fig. 4 of the gas valve; the cap 3 of fig. 4 must be fitted directly on the valve.fig. 4 - Gas conversionKey of main components1 Pressure point upstream2 Ignition "STEP" regulator for liquefied gas3 Plug4 Protection cap5 Pressure adjustment screw for max. power6 Pressure adjustment screw for min. power (1st stage)7 O-ring8 Decrease9 IncreaseV Honeywell valve VR 4601 CBKey of electrical connectionsA + B = Connections fed for min. power (1st stage)A + B + C = Connections fed for max. power (2nd stage)4.2 Commissioning Commissioning must be carried out by Qualified Personnel.The following operations and checks must be made at first lighting, and after all mainte-nance work involving disconnection from the systems or work on safety devices or partsof the boiler.Before lighting the boiler• Open any shutoff valves between the boiler and the system.• Check the tightness of the gas system, proceeding with caution and using soapy wa-ter to check for any leaks in connections.• Fill the water system and make sure all air contained in the boiler and the systemhas been vented by opening the air valve on the boiler and any vent valves in thesystem.• Make sure there are no water leaks in the system or boiler.• Make sure the electrical system is properly connected.• Make sure the unit is connected to an efficient earthing system.• Make sure the pressure and gas flow values are those required for heating.• Make sure there are no flammable liquids or materials in the immediate vicinity ofthe boiler.Lighting the boiler• Open the gas cock ahead of the boiler.• Vent the air from the pipe ahead of the gas valve.• Turn on or insert the switch or plug ahead of the boiler.• Turn the boiler switch (pos. 8 - fig. 1) to position 1.• Turn the knob 7 (fig. 1) to a value above 50°C and that of the room thermostat (ifpresent) to the required temperature. The burner will light and the boiler starts towork automatically, controlled by its adjustment and safety devices. If, after correctly carrying out the lighting procedure , the burners do not lightand the button light comes on, wait about 15 seconds and then press theabove-mentioned button. The reset controller will repeat the ignition cycle. If theburners do not light after the second attempt, consult the sec. 4.4.The boiler switch 8 has 3 positions "0-1-TEST"; the first two have the on-offfunction, the third (unstable) must only be used for service and maintenancepurposes. In case of a power failure while the boiler is working, the burners will go out andrelight automatically when the power is restored.Checks during operation• Make sure the fuel circuit and water systems are tight.• Check the efficiency of the flue and fume ducts while the boiler is working.• Make sure the water is circulating properly between the boiler and the system.• Check correct lighting of the boiler, by turning it on and off several times using theroom thermostat or boiler thermostat.• Make sure the fuel consumption indicated on the meter matches that given in thetechnical data table in cap. 5.Turning offTo temporarily turn the boiler off, just set the boiler switch 8 (fig. 1) to 0.To turn the boiler off for an extended period:• Turn the knob of the boiler switch 8 (fig. 1) to 0;• Close the gas cock ahead of the boiler;• Disconnect the power to the unit; To avoid damage caused by freezing during long idle periods in winter, it is ad-visable to drain all the water from the boiler and the system; or add a suitableantifreeze to the heating system4.3 Maintenance THE FOLLOWING OPERATIONS MUST ONLY BE CARRIED OUT BYQUALIFIED PERSONNEL.Seasonal inspection of the boiler and flueIt is advisable to carry out the following checks at least once a year:• The control and safety devices (gas valve, thermostats, etc.) must function correctly.• The fume ducts must be free of obstructions and leaks.• The gas and water systems must be tight.• The burner and boiler shell must be clean. Follow the instructions in the next section.• The electrodes must be free of deposits and properly positioned (see fig. 11).• The water pressure in the system when cold must be approx. 1 bar; otherwise bringit to that value.• The expansion tank, if present, must be filled.• The gas delivery and pressure must correspond to that given in the technical datatable (see sec. 5.3).• The circulating pumps must not be blocked.Safety devices The boiler PEGASUS 67 ÷ 107 2S is equipped with devices that guarantee safety in case of operation faults.Manual-reset temperature limiter (safety thermostat)This device prevents the water temperature in the system from exceeding boiling point.The maximum activation temperature is 110°C.Resetting of the temperature limiter can only occur on cooling of the boiler (the temper-ature must drop by at least 10°C) and identification and consequent elimination of theproblem that caused the shutdown. To reset the temperature limiter, unscrew the cover3 of fig. 1 and press the button below.

Fume sensor (fume thermostat) safety device The boiler is equipped with a fume evacuation control device (fume sensor - ref. 4 of fig. 1). In case of anomalies in the fume exhaust system with consequent return of burnt gases in the room, the unit shuts down. The antiwind grille is equipped with a tempera- ture sensor bulb for detecting and controlling the fume temperature. Any leaks of burnt gases into the room cause an increase in the temperature detected by the bulb, which causes the boiler to turn off within 2 minutes, shutting off the gas to the burner. If the fume sensor cuts in, unscrew the protection cover (ref. 4 of fig. 1) locat- ed on the control panel and manually reset the device. The boiler will resume operation. If the sensor has to be replaced due to a fault, only use original accessories and ensure that the electrical connections and positioning of the bulb are correctly carried out.

The fume sensor must not be cut out for any reason! Opening the front casing To open the front panel of the boiler, refer to the sequence in fig. 5. fig. 5 - Front panel opening

Before carrying out any operation inside the boiler, disconnect the electrical power supply and close the gas cock upstream. Combustion analysis A fume sampling point has been included inside the boiler, in the top part of the anti- backflow device (see fig. 6). To take the sample:

1. Remove the boiler top panel

2. Remove the insulation placed over the anti-backflow device

3. Open the fume sampling point;

4. Insert the probe;

5. Adjust the boiler temperature to max.

6. Wait 10-15 minutes for the boiler to stabilise*

7. Take the measurement.

Analyses made with an unstabilised boiler can cause measurement errors. Burner assembly removal and cleaning To remove the burner assembly:

• Disconnect the power supply and turn off the gas ahead of the boiler.

• Undo the two screws securing the electronic flame controllers to the gas valve (fig. 7) and remove them from the gas valves (fig. 8).

• For models 97 2S and 107 2S with 2 gas valves, also undo the 2 screws securing the 2 electrical connectors that feed the second valve and remove them.

• Disconnect the ignition and ionisation cables from the electrode assembly.

• Undo the nut fixing the gas supply pipe ahead of the gas valve (fig. 9). For models 97 2S and 107 2S, undo the 2 nuts.

• Undo the two nuts fixing the combustion chamber door to the cast iron elements of the boiler (fig. 10).

• Remove the burner assembly and combustion chamber door. Check and clean the burners. Only use a non-metallic brush or compressed air to clean the burners; never use chemical products. On completion, refit everything in reverse order. fig. 7 - Undo the control unit screws fig. 8 - Remove the control unit fig. 9 - Undo the gas valve nut fig. 10 - Undo the combustion chamber door nuts cod. 3540S433 - Rev. 02 - 04/2018PEGASUS 67 ÷ 107 2S

Pilot burner assembly fig. 11 - Pilot burner 1 Combustion chamber door 2 Inspection door 3 Pilot burner 4 Ignition electrode 5 Detection electrode 6 Pilot nozzle 7 High voltage cable 8 Gas supply pipe Cleaning the boiler and flue For proper cleaning of the boiler (see fig. 12):

• Turn off the gas ahead of the unit and disconnect the power supply

• Remove the front panel of the boiler (fig. 5).

• Lift the casing cover by pressing upwards.

• Remove the insulation 5 covering the anti-backflow device.

• Remove the fume chamber closing plate and insulation.

• Remove the burner assembly (see previous par.)

• Clean from the top downwards, using a flue brush. The same operation can be car- ried out from the bottom upwards.

• Clean the fume evacuation ducts between the cast iron elements of the boiler shell with an aspirator.

• Carefully refit all the previously removed parts and check the tightness of the gas circuit and the combustion ducts.

• During cleaning be careful not to damage the bulb of the fume thermostat fitted on the back of the fume chamber. fig. 12 - Boiler cleaning 1 Casing cover 2 Fume chamber closing plate 3 Flue brush 4 Combustion analysis plug 5 Insulation

To avoid unnecessary expense, before calling the After-Sales Service make sure the boiler has not stopped due to no electricity or gas.

Fault Cause / CureAfter several lighting attempts, the electronic controller shuts down the boiler.Clean the pilot burner nozzles with compressed air.Check the regular gas flow to the boiler and that the air has been eliminated from the pipes.Make sure the electrodes are correctly positioned and free of deposits (see fig. 11).Make sure the boiler is connected to an efficient earth connection.Check the connections at the ignition and ionisation electrodes.The electrodes are not discharging in the ignition phase.Make sure the electrodes are correctly positioned and free of deposits (see fig. 11).Control thermostat adjusted too low.Check the power supply.Check the connections at the ignition and ionisation electrodes.Check the connections at the electronic flame controller.Make sure LINE-NEUTRAL are not inverted and that the earth contacts are effi-cient.Check the inlet gas pressure and any open pressure switches.Reset the safety thermostat.Reset the fume thermostat.Make sure the room thermostat is closed.The burner burns poorly: flames too high, too low or too yellowGas valve filter dirty.Check the gas supply pressure.Gas nozzles dirty.Make sure the boiler is not dirty.Make sure the ventilation in the room where the unit is located is sufficient for proper combustion.Smell of unburnt gas Make sure the boiler is clean.Check the flue draught.Check that gas consumption is not excessive.The boiler works but the tempera-ture does not increaseCheck correct operation of the 2-stage control thermostat.Make sure the gas valve 2nd stage operator (max. power) is fed.Check that gas consumption is not less than that provided for.Make sure the boiler is perfectly clean.Make sure the boiler is adequate for the system.Make sure the heating pump is not blocked.Temperature of water to the system too high or too lowCheck correct operation of the 2-stage control thermostat.Make sure the heating pump is not blocked.Make sure the characteristics of the circulating pump are adequate for the sys- tem. Explosion at burner. Delay on igni- tion Make sure the gas pressure is sufficient and that the boiler shell is not dirty.The control thermostat is reacti-vated with too great a temperature differenceMake sure the bulb is properly inserted in the sheath.Check operation of the 2-stage thermostat .The boiler produces condensate Make sure the boiler is not operating at too low a temperature (below 50°C).Check regular gas consumption.Check the efficiency of the flue.The boiler shuts down for no appar-ent reasonSafety thermostat activation due to an overtemperature.Fume thermostat activation. cod. 3540S433 - Rev. 02 - 04/2018PEGASUS 67 ÷ 107 2S

5.1 Dimensions and connections

fig. 13 - Dimensions and connections Table. 1

5.2 General view and main components

fig. 14 - General view and main components Key 1 Pilot burner assembly 2 Gas valve for all models 3 Electronic flame controller 12 2nd gas valve (only models 107 2S and 97 2S) 13 Boiler drain cock 14 Burner assembly 15 Burner pressure point

Pressure loss Key A Pressure losses m H

Type and model A B C heatingreturn heatingdelivery

Connections in broken lines to be carried out by the installer Key

24 - Ignition electrode

32 - Heating circulating pump (not supplied)

Gas valve (only models 97 2S and 107 2S)

49 - Safety thermostat

72 - Room thermostat (not supplied)

160 - Auxiliary contact

167a - Gas valve 2nd stage operator 167b - 2nd Gas valve 2nd stage operator (only models 97 2S and 107 2S)

170 - 1st stage control thermostat

171 - 2nd stage control thermostat