A unit completely buried under snow: an urgent call in the middle of winter
At AirGreen , our technicians often respond in the middle of winter to central heat pump problems caused by snow and extreme cold. This service call, received one February morning in Boisbriand , on the North Shore of Montreal , perfectly illustrates the risks associated with poor outdoor condenser clearance during the cold season.
The client contacted us after noticing that their TurboAir heat pump was no longer producing heat, despite the thermostat being set to maximum. The house, a typical semi-detached house in the Boisbriand residential area, was cooling rapidly, and the indoor blower was only distributing air at room temperature.
First observation: a condenser under the snow
Upon arriving on site, our team immediately identified the source of the problem. The outdoor unit, a TurboAir central heat pump with approximately 36,000 BTUs, was completely covered in snow and ice . The fan could no longer draw in outside air, and the coil was clogged on all sides.
This situation is more common than you might think: when a heat pump is installed too close to the ground or under an accumulation zone (roof, trees, slope), the melted and then refrozen snow blocks the air circulation necessary for heat transfer. Result: the compressor overheats and the system goes into automatic protection .
Electrical diagnostics and checks
After completely clearing the unit of snow , we undertook a series of technical checks:
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Continuity test on the compressor and fan.
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Voltage measurement at the main contactor (240V confirmed).
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Control board reading : the system displayed an error code related to an “outside temperature fault”.
When measuring the outdoor ambient temperature sensor, we noticed an inconsistent resistance value for ambient -10°C: the sensor was sending a reading equivalent to +25°C, thus preventing the defrost logic from activating.
Intervention and replacement of the probe
We replaced the outside temperature sensor with a genuine TurboAir part, calibrated for this specific model. Before installation, the part was tested with a multimeter to confirm its consistency with real-world outdoor conditions.
Once installed, we ran a full forced defrost cycle using our diagnostic interface. The unit came back to life:
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The compressor has started ,
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The fan has restarted ,
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And the temperature of the internal discharge gradually rose to 36°C.
Preventive maintenance and recommendations
We took advantage of the visit to clean the condenser fins and check the refrigerant pressure . Everything was within the recommended parameters.
Before leaving the premises, we explained to the customer some essential measures to avoid another breakdown:
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Install a protective shelter (awning or mini-roof) over the unit to limit snow accumulation.
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Manually free the unit after each major fall, maintaining a free space of at least 60 cm around it.
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Schedule annual maintenance before winter to ensure the defrost cycle and sensor are working properly.
Result: restored comfort and optimized performance
Within minutes of the repair, the home was back to a stable comfort level , with a constant flow of hot air and balanced pressure. The relieved customer saw that the heat pump was now perfectly responding to the thermostat's demands.
This intervention demonstrates how a simple accumulation of snow can disable a high-performance heat pump. Without adequate clearance, even a modern system can become blocked, causing excessive energy consumption, and even irreversible damage to the compressor.
AirGreen expertise: rapid and preventive intervention
At AirGreen , our approach is based on advanced technical expertise and proactive prevention . Our technicians don't just repair: they identify the root causes of breakdowns to prevent their recurrence. Whether in Boisbriand, Laval , Montreal , or on the South Shore , our interventions guarantee the durability and reliability of each HVAC system.