Intervention in the middle of winter: when snow enters the system
In the heart of the Quebec winter, a resident of Blainville , on the North Shore of Montreal , contacted us about a heating failure on his Fujitsu wall-mounted heat pump . The outdoor unit, installed near a window, was partially buried under snow after several successive storms. This type of situation is unfortunately common during harsh winters: the snow accumulated around the compressor prevents proper air circulation, causing safety shutdowns or abnormal defrost cycles.
At AirGreen , we respond quickly to these types of winter emergencies, as a clogged HVAC system can lead to costly damage to the compressor or control board.
First observation: a stifled outdoor unit
On site, our technician found the Fujitsu Halcyon series compressor, typical of high-performance residential installations, almost entirely covered in snow . The evaporator fins were clogged, and a dense block of ice had formed around the base of the condenser.
The customer noticed that the indoor airflow was decreasing , and that the system was constantly alternating between heating and defrosting , without ever reaching the set temperature.
These symptoms often point us to an outside air circulation problem , aggravated by a buildup of frozen moisture on the coil.
Technical diagnosis: confirm before intervening
Before any mechanical intervention, we carried out a complete analysis of the operating parameters :
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Checking the compressor inrush current (slightly higher than standard);
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Reading of the Fujitsu automatic defrost cycle , the frequency of which was too high (every 20 minutes instead of 60);
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R-410A refrigerant circuit pressure measurement, slightly below nominal values, indicating a temporary restriction caused by frost.
The diagnosis was clear: the heat pump was not suffering from an electrical failure or a lack of gas, but from a mechanical blockage caused by snow and ice .
Step 1: Complete clearance and preventive cleaning
We started by manually clearing snow within a one-meter radius of the unit. Then, a controlled defrosting with hot air was carried out, without the use of chemicals, to avoid any risk to the aluminum fins.
During this step, our technician:
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checked the exterior condensate drain , often frozen at this time of year;
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repositioned the defrost probe , slightly displaced by the frost;
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cleaned the ventilation grille to optimize airflow.
Once the unit was completely clear, we turned the system back on for a performance test.
Step 2: Calibration and adjustments
The restart went smoothly. Blower temperatures quickly reached 41°C, proving that the compressor and external fan were in perfect condition.
We then adjusted the defrost cycle programming via the electronic card — a function that is often overlooked, but essential for adapting the system's behavior to Quebec conditions.
Additionally, we installed a galvanized aluminum deflector shield , designed by AirGreen, to prevent direct snow re-accumulation on the unit. This simple but effective solution extends the life of the compressor and reduces unnecessary defrost cycles.
Step 3: Tips for winter maintenance
At AirGreen , we believe that prevention is the best guarantee of long-lasting performance. After this repair, we shared several practical tips with the customer:
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Maintain a clearance of at least 60 cm around the compressor throughout the winter.
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Never use salt or hot water to defrost an outdoor unit.
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Check drain clearance after every major storm.
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Schedule preventative maintenance at the beginning of each winter to clean, calibrate and check pressures.
These simple actions can prevent 90% of emergency calls related to frost or snow on wall-mounted heat pumps.
A reassured customer and restored comfort
As soon as the intervention was completed, the customer found stable and silent heating , even at -15°C outside.
Our technician provided him with a complete AirGreen maintenance report , including before/after photos and measured operating parameters.
This transparent and rigorous approach is at the heart of our commitment: to offer impeccable technical service, but also lasting peace of mind to each client.
In conclusion
This Fujitsu wall-mounted heat pump repair in Blainville demonstrates the importance of a well-cleared installation adapted to our Quebec winters .
At AirGreen , we combine technical expertise, prevention and knowledge of the local climate to ensure the proper functioning of your HVAC systems — whether you are in Montreal, Laval, Longueuil, on the North Shore or the South Shore .