When a small technical detail hides a big loss of performance
At AirGreen , we often receive calls from customers who are convinced that their HVAC unit is working "halfway." This is exactly the case for this resident of Sainte-Julie , on the South Shore of Montreal , whose Gree wall-mounted heat pump was no longer able to cool the house properly, despite normal operating noise outside.
Diagnosis: a functional heat pump… but ineffective
Upon our arrival, our certified technician performed a complete inspection of the system. The Gree outdoor unit, installed against a brick wall with a well-protected duct run, appeared clean and stable. However, by measuring the refrigerant gas pressure and discharge temperature, we quickly noticed a significant imbalance: the refrigerant level was insufficient .
This situation caused poor cooling , prolonged cycling , and increased energy consumption .
Step 1: Check connections and potential leaks
We carefully checked all flare and braze connections in the system. A very slight leak had developed in the fluid line, likely due to vibration and thermal expansion over time.
Our technicians have:
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Detected the leak using an electronic gas detector ;
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Repaired the connection using a calibrated tightening ;
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Tested for leaks under pressurized nitrogen for 30 minutes to confirm repair.
Step 2: Top up the refrigerant
Once the line was completely sealed, we proceeded to a complete vacuum to remove any residual moisture and air, then recharged the system according to Gree specifications .
The correct dosage of refrigerant is essential: too little reduces performance, too much clogs the compressor.
Result: restored performance and regained energy efficiency
A few minutes after restarting, the difference was obvious:
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The air blown inside went from 19°C to 11°C ;
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The airflow has become stable again;
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The compressor was now operating at full efficiency.
The customer immediately noticed an improvement in ambient comfort. The unit, quiet and smooth, returned to optimal operation—while consuming less energy.
Preventive maintenance tips
At AirGreen, we recommend our clients to:
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Clean the internal filters every two months;
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Monitor for signs of reduced performance (noise, frost, warm air);
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Schedule annual maintenance to inspect the refrigerant and clean the coils.
Preventive maintenance prevents most leaks and optimizes the longevity of your wall-mounted heat pump.
AirGreen Expertise in Sainte-Julie and throughout the metropolitan area
Whether you are in Sainte-Julie, Longueuil, Montreal or Laval , our team responds quickly for any repair of Gree , Midea , Fujitsu , Mitsubishi and other recognized brands of heat pumps.
We make it a point of honor to combine technical rigor , transparency and human service , so that each home finds perfect comfort, summer and winter.