When snow and cold cause a winter breakdown
In the middle of January in Lachine , one of our customers called us about a Fujitsu wall-mounted heat pump that had stopped heating after a heavy snowfall. The outdoor unit, mounted on a wall bracket, was partially covered in ice and snow, preventing the defrost system from functioning properly.
At AirGreen , we know that Greater Montreal's weather conditions can put a strain on HVAC systems, especially wall-mounted heat pumps. A simple buildup of ice around electrical connections or the compressor can be enough to cause a complete breakdown.
Diagnosis: A fault related to ice buildup and a power outage
On site, our technician noted several elements:
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The Fujitsu outdoor unit displayed a flashing red light , indicating a safety shutdown .
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The electrical disconnect box , located next door, was blocked by ice , rendering the circuit breaker inoperable.
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The power cables showed signs of stiffness and frozen condensation , which can cause loss of contact or uneven voltage.
After carefully clearing the area and testing the voltage, the verdict was clear: the system had automatically shut itself down due to a voltage drop caused by moisture and frost around the circuit breaker .
Intervention: recommissioning and prevention of future freezing
The intervention took place in several methodical stages:
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Completely disconnect the power supply before any handling.
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Manual deglazing of the electrical box and bracket using a controlled heat gun.
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Thorough cleaning and drying of cables and connectors using a protective dielectric product.
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Check the automatic defrost circuit (thermistor sensor and electronic card) to ensure the defrost cycle is working properly.
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Fujitsu system soft restart testing , including monitoring of refrigeration pressures and discharge temperature.
We also added extra insulation protection to the refrigerant lines and installed a protective cap on the cut-off box to prevent any future water or snow infiltration.
Result: restored heat and guaranteed prevention
After the complete restart, the Fujitsu heat pump resumed normal operation, automatically switching back to heating mode with a stable and constant flow of hot air.
The customer immediately noticed:
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A rapid return of heat to the main rooms.
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Quiet operation after complete defrosting.
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Optimized energy consumption , thanks to a defrosting cycle that has become efficient again.
We recommended preventative maintenance before each winter , including cleaning the coils, checking the defrost system, and inspecting the wall circuit breaker.
AirGreen expertise: facing Quebec winters with complete peace of mind
This intervention perfectly illustrates the need for regular maintenance of Fujitsu wall-mounted heat pumps and other HVAC systems in the harsh conditions of Greater Montreal . At AirGreen , we respond quickly in Montreal, Laval, Longueuil, on the North Shore and the South Shore to diagnose, repair and protect your devices against the vagaries of the Quebec climate.
Our certified technicians provide:
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Safe repairs even in very cold weather.
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The use of genuine Fujitsu parts and specialized anti-corrosion products.
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Durable solutions to prevent freezing, rust and power outages.
At AirGreen, we ensure that your heat pumps remain reliable, even in the heart of the Quebec winter.