A heat pump that no longer responds: a typical case at the start of the season
At AirGreen , we were recently called about a problem with a Gree wall-mounted heat pump in a residence in Saint-Constant , on the South Shore of Montreal. The customer reported that their unit was no longer producing heat or cool air, despite the indicator light indicating that the unit was powered on.
The installation was about six years old — a period when regular maintenance becomes essential to preserve the performance of the compressor and electronic boards.
On-site diagnosis: a faulty control board
Upon our arrival, our technician performed a complete system check :
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Correct supply voltage to the wall unit.
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No error code displayed, but indoor fan does not start .
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Intact communication between the indoor unit and the outdoor condenser.
After a continuity test and inspection of the electronic board, we confirmed the cause: a failure of the main control board , responsible for managing the fan motor. This problem is often linked to an electrical surge, or to gradual wear due to heat accumulated behind the unit.
Repair: card replacement and full recommissioning
We replaced the control board with an original Gree part, adapted to the exact model of the heat pump. Once installed, we carried out:
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A full system reboot to check the boot sequence.
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Testing the fan and reversing valve (hot/cold changeover).
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A check of refrigeration pressures to ensure that the R-32 refrigerant was circulating correctly.
Result: The system restarted normally, producing warm air at 37°C in heating mode. The customer could see the difference instantly.
A common problem: overheating of electronic cards
Wall-mounted heat pumps installed near the ceiling , like this one, are often exposed to significant residual heat, especially when the room is poorly ventilated. This accumulation can accelerate the deterioration of electronic components and cause sporadic failures.
To prevent this type of breakdown, we recommend:
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Have the filters and coils cleaned twice a year to optimize air circulation.
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Avoid leaving the appliance running continuously at maximum temperature for several days.
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Install a surge protector to secure the board against electrical fluctuations.
AirGreen Tips to Extend the Life of Your Gree Heat Pump
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Maintain the device regularly : preventive maintenance costs much less than replacing the card.
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Check the indicator lights : unusual flashing may indicate a communication or temperature problem.
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Schedule a full diagnostic every two years, especially if the unit operates as both heating and cooling.
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Keep filters clean : A clogged filter strains the motor, increases power consumption and reduces efficiency.
At AirGreen, we know that the reliability of a Gree system depends on a balance between good maintenance, regular electrical checks and genuine parts.
AirGreen: your HVAC expert on the South Shore and in Greater Montreal
Our team operates daily in Montreal, Laval, Longueuil, and throughout the South Shore and North Shore , for the repair, maintenance and replacement of wall-mounted heat pumps of all brands: Gree, Fujitsu, Midea, Sharp, Zephyr, Goodman, Bosch , and many others.
We offer professional, fast and transparent service — no hidden costs, detailed diagnostics and a warranty on replaced parts.
Final result in Saint-Constant
After replacing the control board, the Gree wall-mounted heat pump returned to full performance. The customer was able to enjoy optimal comfort, without excessive noise or temperature fluctuations.
A simple, but crucial intervention, demonstrating the importance of regular preventive maintenance and professional electronic control .