An outdoor unit put to the test by the Quebec winter
When a harsh winter hits the North Shore, HVAC systems are subjected to extreme conditions. At AirGreen , we often receive service calls during this time of year, especially for central heat pumps whose outdoor units struggle to operate in the snow and frost.
This is exactly the case of a customer from Sainte-Thérèse , who contacted us after noticing that his Goodman heat pump stopped heating in very cold weather and that the outdoor fan remained stationary despite the thermostat requesting heat.
Initial diagnosis: a unit covered in ice and a blocked fan
When we arrived, the situation was clear: the outdoor unit, placed on the ground without any elevation, was partially buried under hardened snow . The customer had attempted to clear the area around the unit, but a mass of ice had formed on the bottom of the condenser , preventing the fan from rotating freely.
Our initial observations:
-
Significant ice buildup on the outdoor coil .
-
Clicking noises coming from the compressor when trying to start.
-
Main fan blocked by a mixture of ice and debris.
-
Power wiring intact , but moisture present at the lower connectors.
We therefore initiated a full diagnostic to determine if the fan motor or the control board had suffered damage.
Diagnostic steps and technical checks
Our certified technicians proceeded methodically:
-
Complete power cut to secure the intervention.
-
Fan motor resistance measurement — values indicated intact winding (approximately 35 Ω between main terminals).
-
Start capacitor check : capacitance lower than standard, measured at 5.8 µF instead of 7.5 µF.
-
Visual inspection of the control board : slight oxidation on the lower connectors, caused by repeated ice melting.
-
Complete steam cleaning of the coil to remove the compact ice layer.
These tests confirmed that the motor start capacitor needed to be replaced and that the electronic board required cleaning and anti-humidity treatment.
Repair and recommissioning
The repair involved several key steps:
-
Replacement of the starting capacitor with an original Goodman model, nominal voltage 440V.
-
Applying a dielectric protective spray to exposed connectors.
-
Realigned the top cover and checked the airflow .
-
Repositioning the unit on a raised composite support , to prevent future snow accumulation.
After these interventions, the heat pump was restarted. The fan started immediately, the compressor followed without abnormal noise and the pressure measured on the refrigeration circuit quickly stabilized at optimal values for operation in cold weather.
Result: restored performance and improved efficiency
Once the heat pump was put back into service, performance measurements confirmed a coefficient of performance (COP) in line with the manufacturer's specifications, even at -10°C.
The client was able to observe:
-
Constant heat throughout the house ,
-
A reduction in external noise ,
-
Stabilized electricity consumption .
We took advantage of the visit to explain to the customer how to protect his outdoor unit in winter :
-
Maintain a clear area of at least 60 cm around the condenser,
-
Avoid covering the unit with waterproof tarpaulins which trap moisture,
-
And have the automatic defrosting system checked every fall before the first snow.
The importance of preventive maintenance on the North Shore
Winters in Sainte-Thérèse and surrounding areas (Blainville, Boisbriand, Rosemère) put HVAC systems to the test. A central heat pump must be able to efficiently manage frost, snow and defrost cycles .
At AirGreen, we emphasize prevention: professional annual maintenance not only extends the life of the compressor, but also preserves the energy efficiency of the system .
Our RBQ and EPA certified technicians carry out:
-
Complete inspection of electrical connections ,
-
The test of pressures and refrigeration efficiency ,
-
Cleaning the coil and the drainage tray ,
-
Calibration of automatic defrosting (outdoor temperature sensor and thermistor) .
AirGreen: your HVAC reference in Sainte-Thérèse and on the North Shore
This repair perfectly illustrates AirGreen's expertise in diagnosing and repairing central heat pumps .
Whether it's a compressor breakdown, a faulty electronic board, or a simple worn-out electrical component, our team has the measuring tools and original parts to intervene effectively, even in the middle of winter.
We serve Sainte-Thérèse, Blainville, Boisbriand, Terrebonne and Laval daily, ensuring fast, guaranteed service that meets the most demanding HVAC standards .