Q: What does the error code PP 0 mean on a GRE pool heat pump and how can it be resolved?

The error code PP 0 on GRE pool heat pumps (models HPG25, HPG40, HPG50, HPG70) indicates a protection against low ambient temperatures . This means that the outside air temperature is too low to allow the device to operate normally. The HPG heat pumps operate at ambient temperatures between 7 °C and 43 °C . When the outside temperature drops below 7 °C, the system automatically activates this protection and interrupts the heating of the pool to prevent compressor failure. For optimal and efficient use, a minimum ambient temperature of 10 °C is recommended. First, check the weather conditions. If the outside temperature is below 10 °C, wait for a warming period or use your heat pump during the warmer parts of the day. If the temperature exceeds 10 °C and the error persists, proceed with the following checks. Inspect the ambient temperature sensor by ensuring that all its electrical connections are secure and show no signs of corrosion. Completely restart the pump by cutting off the power for at least 30 seconds, then restore power. The error code should disappear once the weather conditions become favorable again. If the error code reappears regularly at correct temperatures (above 10 °C), this may indicate a failure of the ambient temperature sensor. In this case, contact a qualified technician or a specialized installer for inspection and possible replacement of the sensor.

Question 1

How to correctly position the O-ring on the cover of the GRE PP031 filtration pump?

Accepted Answer

To ensure the sealing of your GRE PP031 filtration pump, it is essential to correctly position the O-ring on the cover. Here’s how to proceed:

Steps to position the O-ring:

Inspect the O-ring: Check that it is intact, without cracks or deformations to ensure good sealing.
Locate the dedicated groove: On the inner edge of the pump cover, locate the circular groove designed to accommodate the O-ring.
Place the O-ring: Carefully insert the O-ring into the groove, ensuring it is well positioned, without twisting or folding.
Check the fit: Make sure the O-ring rests evenly in the groove all around its circumference.
Close the cover: Once the O-ring is in place, you can close the cover, ensuring it fits properly to avoid any leaks.

A well-positioned O-ring ensures optimal sealing and extends the lifespan of your pump.

Question 2

How to proceed with the first use of the GRE pool heat pump HPM20, HPM30, or HPM40?

Accepted Answer

For the first use of your GRE pool heat pump models HPM20, HPM30, or HPM40, follow these essential steps to ensure optimal operation:

1. Correct installation

Place the heat pump in a well-ventilated area, protected from debris and bad weather, on a stable and flat surface. Ensure that the installation complies with current electrical and plumbing standards.

2. Electrical connection

Check that the pump is connected to a power supply that meets the model specifications. The connection must be secure and protected from moisture.

3. Pool preparation

Ensure that the pool is filled to an adequate level so that the pump can operate correctly without risk of overheating or damage.

4. Starting and settings

Turn on the heat pump via the control panel.
Set the desired temperature for water heating according to your needs.
Check that the pump is in heating mode.

5. Initial monitoring

Monitor the operation of the pump during the first few hours to ensure that it heats correctly and that no malfunctions occur.

These steps ensure an effective and safe commissioning of your GRE heat pump. If in doubt, check the connections and the installation environment to avoid any issues.

Question 3

Why is my GRE HPM40 heat pump blowing cold air and discharging cold water into my pool?

Accepted Answer

Important: The cold air blown by your HPM40 heat pump is actually a sign of proper functioning, not a malfunction. By design, your heat pump extracts heat from the outside air to transfer it to your pool water. The air that comes out is therefore cooled during this thermodynamic process, which is completely normal and expected.

If you also notice that the pool water is not heating despite this cold air being blown, first check three essential conditions. First, the filtration pump must be running: your HPM40 only operates when the filtration system is circulating. Second, the ambient temperature must be at least 12°C for the pump to start (it activates a built-in protection below this threshold). Third, check the set temperature on the LED controller: the HPM40 heats towards the target temperature you have programmed between 10°C and 42°C.

If these three points are met but the water is not warming up, check the condition of the evaporator. Leaves, debris, and dirt can obstruct the fins of the evaporator (the part that captures heat from the air), drastically reducing performance. Regularly clean the air intake and clear the area around the unit to ensure good circulation of fresh air. The HPM40 delivers a power output of 5.5 kW under optimal conditions (air 28°C / water 28°C), but this performance depends on unobstructed air intake.

Be aware that heating takes time. Depending on the initial temperature of your pool and the ambient air temperature, several days of continuous operation (24/7) may be necessary to reach the desired temperature. A good pool cover (solar or thermal blanket) will significantly reduce this time by limiting heat loss.

If after these checks the water remains cold, two technical problems are possible. The water temperature sensor or the ambient temperature sensor may be faulty (open circuit or short circuit), preventing proper regulation. You will then see error code P1 or P2 on the LED screen. Another possibility: a refrigerant leak (R32 for the HPM40) or a gas circuit pressure issue. In these cases, hire a qualified technician to work on the cooling circuit, as these elements require expertise and specialized equipment.

In summary, start by checking the filtration, ambient temperature, thermostat setting, and the condition of the evaporator. Normal operation combines cold air being blown and a gradual warming of the water. Regular maintenance and adherence to installation conditions optimize the performance of your HPM40.

Question 4

Where are the temperature sensor connections located on GRE heat pumps models HPG25 to HPG70?

Accepted Answer

The temperature sensor connections on GRE heat pumps models HPG25, HPG40, HPG50, and HPG70 are generally located inside the unit. Here’s how to locate them:

Locating the temperature sensor connections

Location: The temperature sensor is often mounted near the evaporator coil or close to the compressor, where it can accurately measure the fluid temperature.
Access: To access the connections, it is necessary to open the heat pump casing. This usually involves removing the screws or clips that hold the access panel in place.

Precautions before intervention

Disconnect the power supply: Ensure that the heat pump is completely unplugged from the mains to avoid any risk of electric shock.
Handling: Handle the internal components carefully to avoid damaging the sensors or wiring.

Checking the connections

Once the sensor is located, check that the electrical connections are secure and in good condition, without corrosion or loose wires.
If you notice a problem, it may be necessary to replace the sensor or tighten the connections.

This operation may require technical knowledge. If you are not comfortable with this type of intervention, it is recommended to call a qualified professional.

Question 5

What does the error code PP 0 mean on a GRE pool heat pump and how can it be resolved?

Accepted Answer

The error code PP 0 on GRE pool heat pumps (models HPG25, HPG40, HPG50, HPG70) indicates a protection against low ambient temperatures. This means that the outside air temperature is too low to allow the device to operate normally.

The HPG heat pumps operate at ambient temperatures between 7 °C and 43 °C. When the outside temperature drops below 7 °C, the system automatically activates this protection and interrupts the heating of the pool to prevent compressor failure. For optimal and efficient use, a minimum ambient temperature of 10 °C is recommended.

First, check the weather conditions. If the outside temperature is below 10 °C, wait for a warming period or use your heat pump during the warmer parts of the day. If the temperature exceeds 10 °C and the error persists, proceed with the following checks.

Inspect the ambient temperature sensor by ensuring that all its electrical connections are secure and show no signs of corrosion. Completely restart the pump by cutting off the power for at least 30 seconds, then restore power. The error code should disappear once the weather conditions become favorable again.

If the error code reappears regularly at correct temperatures (above 10 °C), this may indicate a failure of the ambient temperature sensor. In this case, contact a qualified technician or a specialized installer for inspection and possible replacement of the sensor.

Question 6

How to obtain spare parts for the GRE water pump model PP052?

Accepted Answer

To obtain spare parts for your GRE water pump model PP052, here are the steps to follow:

Contact GRE customer service: The manufacturer is the main source for ordering original parts suitable for your model. You can reach them by phone or through their official website.
Check authorized dealers: Some distributors or specialized stores in plumbing equipment and water pumps may offer compatible parts.
Precisely identify the necessary part: Note the reference or exact description of the part to facilitate the search and ordering process.
Consult forums and specialized websites: Sometimes, users share tips or reliable sources for purchasing spare parts for this model.

By following these tips, you will be able to easily find and order the spare parts suitable for your GRE PP052 pump to ensure its maintenance or repair.

User manual GRE : user manuals and guides in PDF

Models GRE most viewed

Browse manuals GRE by appliance type

Recent questions about devices GRE