Intervention on a sunny roof: diagnosis and rapid repair
At AirGreen , every service call is an opportunity to demonstrate our expertise in HVAC system repair . Recently, our team was called to Sainte-Julie , on the South Shore of Montreal , for a problem with a Midea heat pump installed on the roof of a small commercial building. The outdoor unit, exposed to the elements, was no longer responding correctly to thermostat commands.
After a few phone calls, the customer confirmed that the system had not been producing heat or air conditioning for two days, despite the circuit breaker being reset. We scheduled a visit the next morning, taking advantage of the ideal weather for a roof inspection.
Accurate diagnosis: a partial power failure
Upon our arrival, our technicians inspected the Midea outdoor condenser , securely mounted on an aluminum support, raised to avoid any contact with the gravel on the roof.
Our initial measurements revealed an unstable electrical voltage on the power terminal: a broken phase was preventing the compressor from starting.
To confirm our hypothesis, we carried out:
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a continuity test of the wiring between the main panel and the condenser;
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a check of the protective fuses located near the unit;
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a check of the main contactor and the control module .
The result: a faulty thermal fuse in the outdoor breaker box. This small, often overlooked component had blown due to a temporary short circuit caused by moisture.
Complete repair and return to service
We replaced the fuse , followed by a complete cleaning of the electrical compartment. To prevent any recurrence, a wiring insulation test was carried out to ensure that no water infiltration persists.
Once the power was restored, the heat pump restarted without difficulty. We then:
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checked the R-32 refrigerant pressures , perfectly stable;
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controlled the fan speed and indoor blowing temperature ;
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confirmed stable communication between indoor and outdoor units .
The Midea heat pump has returned to optimal operation, with excellent performance in air conditioning mode.
AirGreen expertise: rigor and prevention
This type of intervention perfectly illustrates our approach: a precise diagnosis , without unnecessary replacement of parts, and effective prevention of future problems.
Our technicians also have:
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added an extra gasket around the exterior electrical box cover;
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advised the customer to perform a complete annual check , including cleaning the coil and calibrating the thermostat.
Thanks to this rigor, the system's lifespan is extended and its energy efficiency maintained at an optimal level.
Professional service in Sainte-Julie and throughout the South Shore
At AirGreen , we operate throughout the South Shore , in Sainte-Julie, Brossard, Boucherville, Saint-Lambert and many other municipalities. Our certified technicians specialize in brands like Midea, Fujitsu, Sharp, Gree, Goodman and Trane , for all types of wall-mounted, multi-zone or central systems.
Each repair is carried out with original parts , in compliance with the manufacturer's standards and Quebec building codes.
In conclusion: performance and peace of mind restored
Thanks to a quick and careful intervention, our Sainte-Julie client has regained all the comfort of his Midea heat pump, ready to face the climatic variations of Quebec.
This project perfectly reflects our mission: to offer a reliable, transparent and sustainable HVAC service , always focused on customer satisfaction and long-term equipment performance.