Repair of a Gree wall-mounted air conditioner in Sainte-Dorothée

When Neglected Maintenance Causes a Complete Shutdown

At AirGreen , we often receive urgent calls in the middle of summer, when the heat becomes unbearable. This is exactly what happened in Sainte-Dorothée , Laval, when one of our customers contacted us because their Gree wall-mounted air conditioner had suddenly stopped working. The indoor unit, mounted high on a living room wall, was no longer responding to the remote control, and no indicator lights were coming on.

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Initial diagnosis: a breakdown that seemed trivial

Upon arrival, we proceeded with our standard diagnostic procedure :

• Checking the power supply to the wall unit;

• Inspection of the fuses and circuit breaker connected to the heat pump;

• Check the voltage at the indoor unit terminal block;

• Visual check of the electronic board and temperature sensor.

We quickly discovered that moisture and dust accumulated inside the unit had damaged a section of the main control board . The customer had not performed a thorough cleaning in over three years, which had contributed to the fouling of the fan and evaporator coil.

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Repair: Deep cleaning and card replacement

Our technicians carefully disassembled the unit to perform a complete cleaning of the interior module , following these steps:

1. Removing the front panel and washable air filters;

2. Spraying AirGreen biodegradable cleaner on the evaporator fins;

3. Pressure-controlled rinsing to remove dust and mold;

4. Dry with compressed air to avoid any residual moisture;

5. Installation of a new original Gree control board , calibrated according to the unit's serial number.

After replacement, we restored power and tested the unit: the indoor fan started up again immediately, followed by a steady blast of cool air.

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Performance testing and final verification

To ensure a lasting repair, our team carried out:

• A blowing temperature measurement (14°C in cold mode at medium speed);

• R-32 refrigerant pressure control via the outdoor unit;

• A check of communications between the indoor board and the outdoor module.

The observed values ​​were perfectly in line with the manufacturer's specifications, confirming optimal return to service .

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Maintenance advice provided to the customer

We took the time to explain to the customer that this type of breakdown could be avoided through annual preventive maintenance .
Our recommendations:

• Clean filters every 4 to 6 weeks during the summer;

• Perform a complete professional cleaning every year ;

• Avoid disconnecting the unit's power supply during the winter, as some electronic boards require constant voltage to maintain their configuration.

The customer also chose to join our AirGreen maintenance program , which includes an annual visit, refrigerant check, full cleaning and performance verification.

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Result: comfort restored and customer reassured

Following the intervention, the Sainte-Dorothée residence immediately regained comfort. The Gree unit now operates quietly and efficiently , with balanced airflow and a stable temperature.

This case perfectly illustrates the importance of regular monitoring of any HVAC system . At AirGreen, we work on all brands— Gree, Fujitsu, Sharp, Midea, Goodman, Zephyr, Bosch, Trane , and more—in the Montreal, Laval, Longueuil, North Shore, and South Shore regions.

Whether it's an urgent repair , preventative maintenance or an in-depth diagnosis , our certified technicians guarantee fast, transparent and lasting service.

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AirGreen – Your specialist in HVAC system repair and maintenance in Laval and throughout Greater Montreal.