A service call for loss of cooling efficiency
At AirGreen , we are often called out for performance issues with wall-mounted heat pump systems . This was the case for this client located in Verdun , Montreal, whose Gree heat pump was no longer producing enough cold in early spring. Despite normal compressor and fan noise, the blowing temperature remained lukewarm—a typical sign of a refrigerant leak .
Precise diagnosis: leak detection and pressure test
Upon our arrival, our AirGreen technician conducted a complete inspection of the system . The outdoor unit, mounted against a brick wall, showed clear signs of previous work: partially detached insulation and a slight deposit of oil on the base of the unit. These clues already guided our diagnosis.
We followed our AirGreen diagnostic procedure in several steps:
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Pressure monitoring using a digital manifold connected to the refrigeration circuit. Static pressures were abnormally low, confirming a pressure drop.
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Thorough visual inspection : slight oil seepage was visible on a weld near the compressor.
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Nitrogen test : We injected high-pressure dry nitrogen into the system to locate the leak. Bubbles appeared at a poorly sealed brazed connection .
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Further verification using an electronic detector : the device confirmed the presence of R-32 refrigerant around this same area.
Leak repair and recharge with R-32 refrigerant
Once the leak was identified, our technician undertook the complete repair of the refrigeration circuit :
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Complete purging and recovery of residual gas in accordance with environmental standards.
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Replacement of the defective pipe section and rework of the silver brazing to ensure a perfect seal.
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Retested with nitrogen pressure for 30 minutes to ensure no leaks were present.
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Complete emptying of the circuit using the vacuum pump until a stable pressure of less than 500 microns is reached.
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Accurate recharge with R-32 refrigerant according to Gree manufacturer's specifications.
Once the recharge was complete, we restarted the heat pump and measured:
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a stable suction pressure ,
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an indoor/outdoor temperature difference of 11°C ,
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and a cooling efficiency in line with the model's nominal range.
Result: restored comfort and optimal performance
As soon as the intervention was completed, the customer noticed a marked improvement: the blown air was fresh and constant, and the interior temperature dropped quickly. The compressor operated without vibration or abnormal noise.
We took the time to clean the casing and coils , then replaced the internal sound insulation. Finally, we recommended annual preventative maintenance to the customer, including a check of the refrigeration circuit and air flow to prevent any recurrence.
AirGreen Recommendations to Avoid Future Leaks
A refrigerant leak is often caused by:
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excessive vibration of the outdoor unit,
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a weld weakened by freezing/thawing,
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or bad installation media .
To prevent this type of breakdown, our experts advise:
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Have system pressures checked annually before the hot season.
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Visually inspect the lines for oil.
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Avoid structural vibrations by ensuring stable mounting on a rust-proof wall bracket.
AirGreen: your expert in Gree wall-mounted heat pumps in Verdun and throughout Greater Montreal
Our team specializes in the repair and maintenance of Gree systems , as well as other brands such as Midea, Sharp, Fujitsu, Goodman and Lennox . We respond quickly in Montreal, Laval, Longueuil, on the North Shore and the South Shore , with EPA-certified technicians and precision tools .
At AirGreen , every intervention is carried out with rigor and transparency. Our priority: restoring the comfort of your home while maximizing the lifespan of your HVAC system .