Heating failure in a brick house: our team takes action
One spring morning in Saint-Lambert , a customer contacted us urgently about a complete breakdown of their Comfortmaker central heat pump . The outdoor unit, installed on the side wall of a typical South Shore brick house, would no longer start. During a transitional period when nights remain cool, indoor comfort depended entirely on the proper functioning of the HVAC system.
At AirGreen , we know how frustrating these outages can be, so we dispatched a certified technician to your location the same day.
Initial diagnosis: a silent compressor and a stationary fan
Upon our arrival, the customer had already checked the circuit breaker and thermostat, but there was no sign of activity coming from the outdoor condenser. The fan was not spinning, and no voltage was being transmitted to the compressor.
Our measurements revealed:
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Correct power supply to the outdoor unit.
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No voltage to the fan motor.
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Abnormal voltage on the main contactor , suggesting a control fault.
So we opened the service panel to inspect the internal components.
The cause: a burnt power contactor
Visual examination quickly confirmed our hypothesis:
➡️ The power contactor showed signs of burning and oxidation , preventing current flow to the compressor and fan motor.
This component, often overlooked during maintenance, acts as a relay between the internal control (thermostat) and the start of the high-voltage circuit. When it deteriorates, the heat pump becomes completely inoperable.
Intervention: replacement of the contactor and complete check of the circuit
We completely replaced the contactor with an original Comfortmaker part, compatible with the customer's central heat pump model.
Then we have:
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Cleaned the electrical terminals to ensure good contact.
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Tightened the compressor and motor connections .
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Checked the capacitor : the measured capacitance was still within specifications (43 µF for 45 µF nominal).
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Tested the 24V control voltage from the internal board.
After powering up, the system restarted normally: the compressor started, the fan reached its nominal speed, and warm air immediately began circulating in the house.
Final checks and performance test
To confirm the success of the intervention, our technician carried out a series of measurements:
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Refrigerant circuit pressure : 120 psi low pressure, 260 psi high pressure (normal values).
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Air temperature at the register : 32°C in heating mode.
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Power consumption : stable and compliant.
No abnormal noise or excessive vibration was detected, indicating a complete recovery of the thermal performance of the Comfortmaker system.
Maintenance advice given to the customer
We took advantage of the intervention to raise awareness among the client about the importance of annual preventative maintenance , particularly for central heat pumps.
Here are the recommended points:
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Clean the exterior coils regularly with fresh water.
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Check the base of the unit , which must be stable and clear of any obstructions.
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Replace the internal filter every 2 to 3 months.
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Have the contactor and capacitor inspected every spring before the warm season.
These simple checks prevent most electrical failures, like the one encountered in this house in Saint-Lambert.
A Comfortmaker HVAC system ready for the seasons to come
Thanks to our rapid intervention, the client was able to regain thermal comfort in his home without having to replace the entire equipment. The Comfortmaker system , renowned for its robustness and efficiency, can now operate for several additional years with regular maintenance.
At AirGreen , we work daily on central and wall-mounted systems throughout Greater Montreal, whether for brands like Comfortmaker, Trane, Goodman, Lennox, Fujitsu or Midea .
Our approach is based on precise diagnosis , original parts , and fast, professional service that restores our customers' confidence.
In conclusion
This repair in Saint-Lambert demonstrates that a central heat pump failure doesn't necessarily require a complete replacement. Thanks to our HVAC diagnostic expertise, we were able to identify and resolve the exact cause—a simple burnt-out contactor—and restore the customer's expected performance from their Comfortmaker system.
Another concrete example of AirGreen's expertise in the service of Montreal home comfort.