A quick service call for a faulty LG air conditioner
At AirGreen , we often receive calls from Montreal customers experiencing air conditioning issues during periods of intense heat. On this day, our team was working in a red brick residential building in the Villeray–Saint-Michel–Parc-Extension area, where an LG wall-mounted air conditioner was operating intermittently.
The customer contacted us after noticing that their outdoor unit—a wall-mounted LG compressor —was suddenly starting and stopping, without the indoor unit providing consistent cool air. This is a common occurrence in urban environments where dust, humidity, and aging hardware can affect system performance.
Complete on-site diagnosis
Upon our arrival, we carried out a complete diagnosis:
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Visual inspection of the outdoor condenser attached to the brick wall: no major obstructions, but presence of dirt on the fan grill.
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Electrical check : correct voltage at the circuit breaker output.
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R-410A refrigerant pressure analysis : slightly lower than normal.
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Check the electronic card : some traces of oxidation, a sign of humidity infiltration.
After these tests, we determined that the fault was caused by a faulty board relay , preventing the compressor from maintaining a stable cycle.
Repair and recommissioning
We proceeded as follows:
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Complete cleaning of the condenser and fan surface using a biodegradable cleaner specific to HVAC systems.
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Replacing the relay on the power supply circuit board.
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Checking the R-410A refrigerant charge and adjusting it according to LG nominal pressures.
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Full performance test over 30 minutes of continuous operation.
The wall-mounted air conditioner has returned to optimal operation , providing a stable temperature and a quiet cycle. We also advised the customer to schedule annual preventive maintenance , especially before the summer season, to avoid clogging and short circuits related to humidity.
AirGreen Expertise: Precision and Sustainability
Every service call is an opportunity for our team to demonstrate AirGreen's expertise in residential HVAC repair . Our technicians are trained to work on all major brands— LG, Fujitsu, Midea, Sharp, Gree, Zephyr, and more—and have the tools to perform accurate diagnostics without unnecessarily replacing functional parts.
We emphasize the importance of regular maintenance for:
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Maintain the energy efficiency of the system.
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Reduce electricity consumption.
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Extend the life of the compressor and wall unit.
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Ensure constant comfort even during heat waves.
Maintenance Tips for LG Air Conditioner Owners
To avoid this type of breakdown, here are some simple steps to take:
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Clean the internal filter every two to three weeks during the summer.
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Avoid obstructing the outdoor unit with plants, objects or shade cloths.
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Have the refrigerant gas pressure checked by a professional every two years.
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Schedule a complete spring maintenance with a certified team.
A well-maintained air conditioner uses up to 20% less energy and provides a more consistent temperature in every room.
Final result
At the end of our intervention, the client regained optimal comfort in his apartment. His LG wall-mounted air conditioner, securely mounted to the brick facade, is now operating at perfect efficiency. This type of repair, carried out quickly and accurately, demonstrates our commitment to providing reliable, efficient, and local service in the heart of Montreal and its residential neighborhoods.
At AirGreen , we believe that HVAC repair service is about more than just replacing parts—it's about restoring confidence and comfort to our customers, while ensuring the long-lasting performance of their equipment.