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Réparation d’une thermopompe Mitsubishi Electric à Rosemère
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Mitsubishi Electric heat pump repair in Rosemère

A breakdown in the middle of winter: an urgent call for an essential heating system

At AirGreen , we know that a heat pump breakdown in winter can quickly become critical, especially during Quebec's intense cold. This is precisely the situation encountered by a customer in Rosemère , on the North Shore of Montreal , when their Mitsubishi Electric heat pump stopped heating while the outside temperature was around -15°C.

Initial diagnosis: a lack of refrigerant is the cause

Upon arrival, our technician noticed that the outdoor fan was running, but the compressor was failing to reach the pressure needed to generate heat. The customer reported that for several days, the unit had been blowing lukewarm air, which was insufficient to heat the house.

After inspection, initial checks revealed:

  • Very low refrigerant pressure , detected using a set of electronic pressure gauges connected to the unit.

  • No frost on the coils , a sign that the refrigeration circuit was not complete.

  • No active alarm on the electronic card , excluding a control failure.

These observations pointed the diagnosis towards a leak of R410A refrigerant .

Technical intervention: leak detection and complete recharge

Our specialists undertook a comprehensive intervention despite the winter conditions. Here are the main stages of the service:

  1. Nitrogen pressure test to locate leak: minimal leak detected on a solder joint of the service connection at the rear of the condenser.

  2. Repair of the defective joint by silver soldering, carried out with portable equipment suitable for low temperatures.

  3. Extended vacuum to remove all traces of moisture from the circuit.

  4. Complete system recharge with R410A , calibrated according to the manufacturer's specifications Mitsubishi Electric.

  5. Checking the automatic defrost cycle , essential to ensure performance in cold climates.

The entire operation was carried out with rigor and safety, in accordance with current environmental standards for handling refrigerant gases.

Performance tests: efficiency restored to 100%

Once the repair was complete, our technicians carried out a series of tests to validate the proper functioning of the heat pump:

  • Balanced pressures according to the technical data of the H2i range.

  • Indoor blowing temperature of 42°C , confirming optimal performance.

  • Automatic defrost cycle activated and stabilized after 45 minutes of continuous operation.

The client immediately noticed a return to comfortable warmth throughout the house. The Mitsubishi Electric heat pump, renowned for its low-temperature performance, regained its ability to operate efficiently even in sub-zero temperatures.

AirGreen Tips to Maximize Winter Sustainability

To avoid this type of recurring breakdown, our team has recommended some essential practices:

  • Have the refrigeration connections inspected every fall before the cold season.

  • Clear snow and ice around the outdoor unit to prevent air obstructions.

  • Check that the defrost cycle is working properly to prevent frost buildup.

  • Subscribe to an AirGreen maintenance plan , including two annual visits (spring and fall).

These measures not only help extend the life of the equipment, but also ensure constant comfort throughout the year.

Expertise and reliability signed AirGreen

At AirGreen, we service all types of residential and commercial HVAC systems, specializing in Mitsubishi Electric, Fujitsu, Gree, Lennox, and Midea wall-mounted and central heat pumps . Our certified technicians have the most accurate diagnostic equipment on the market, ensuring fast and lasting repairs, even in extreme conditions.

Our reputation is based on:

  • Fast and professional interventions throughout Montreal, Laval, Longueuil, the North Shore and the South Shore.

  • Transparent service procedures that comply with manufacturer standards.

  • A preventive approach that protects our clients' investments in the long term.

Final result: comfort restored despite the storm

Thanks to efficient and meticulous work, the customer's Mitsubishi Electric heat pump in Rosemère is now operating at full capacity. The system is once again heating efficiently, without any loss of efficiency, and energy consumption has returned to normal levels.

Another success from AirGreen , where technical expertise and reliability combine to offer the best in HVAC comfort throughout Greater Montreal.