A silent indoor unit… but without cooling
An Outremont resident recently contacted us about a broken LG wall-mounted air conditioner installed in an elegant, classic-style home. The unit appeared to be operating normally: the interior fan was blowing air , no error codes appeared on the screen, but the air remained lukewarm , even in maximum cooling mode.
This type of symptom is common on wall-mounted HVAC systems after several seasons of use, especially when preventative maintenance has not been performed for some time.
Initial diagnosis: a lack of refrigerant detected
Upon our arrival, we carried out a complete inspection of the refrigeration circuit . The outdoor unit, installed on the roof of the house, appeared clean and without any signs of apparent leaks. However, our pressure measurements quickly confirmed an abnormally low pressure , indicating a partial loss of refrigerant gas (R410A) .
Electronic detector analysis enabled the location of a micro-leak at the suction pipe connection – a sensitive point often subject to compressor vibrations.
Steps of repair
Our team undertook the repair methodically:
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Complete cut-off of the power supply to secure the intervention.
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Partial disassembly of the outdoor unit casing to access the service valves.
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Tightening and repair of the weld on the affected suction line.
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Nitrogen leak test to ensure no further leaks remained.
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Complete vacuuming of the circuit to eliminate all traces of humidity.
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Accurate refill with R410A refrigerant , calibrated according to the length of the pipe and the specifications of the LG manufacturer.
Once the system was powered up again, we observed a stabilization of pressures and a clear improvement in thermal efficiency .
Results: restored performance and comfort regained
As soon as the intervention was completed, the air blown by the wall unit reached 9°C at the outlet , proof that the heat pump was working at full capacity. The delighted customer immediately felt the difference: a cool and stable interior temperature, without excessive noise or vibration.
To ensure the longevity of the installation, we recommended:
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A complete annual maintenance including cleaning the coil, checking the drain and checking the pressures.
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A visual inspection at the start of each season to detect any traces of oil around the fittings.
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The possible installation of anti-vibration supports to reduce the movement of refrigeration pipes.
AirGreen Expertise in Outremont
At AirGreen , we have built our reputation on the quality and rigor of our interventions . Our technicians are trained to quickly diagnose breakdowns of heat pumps and wall-mounted air conditioners from LG, Fujitsu, Midea, Sharp, Gree, Zephyr , and many other brands.
Our approach always favors:
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An accurate diagnosis before any part replacement .
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Sustainable repairs that meet environmental standards.
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Transparent communication with the customer at every stage.
Why Choose AirGreen for Your HVAC Repairs
Whether you are in Montreal, Laval, Longueuil, on the North Shore or the South Shore , our teams respond quickly to resolve any heating, ventilation and air conditioning problem. Each service is documented, accompanied by clear recommendations and personalized follow-up.
Our goal: to ensure optimal comfort all year round , while maximizing the lifespan of your HVAC equipment.
Conclusion
This LG wall-mounted air conditioner repair in Outremont demonstrates how a simple microleak can compromise the performance of an HVAC system. Thanks to a quick and meticulous intervention, AirGreen was able to restore the customer's comfort and extend the useful life of their unit.
At AirGreen, every service call is an opportunity to demonstrate our commitment to quality, reliability and lasting customer satisfaction across the greater Montreal area.