A typical urban service call: speed, safety and expertise
At AirGreen , we frequently receive service calls for HVAC systems installed on flat roofs in Montreal and the surrounding area. This type of installation, common in apartment buildings and small businesses, requires a rigorous approach—both for secure access and for accurate diagnosis of units exposed to the elements.
Recently, our team intervened in Lachine , in a multi-unit residential building, for an urgent repair of a Goodman heat pump . The outdoor unit, installed on the roof, was no longer starting despite the heating controls.
On-site diagnosis: an electrical fault linked to humidity
Upon arrival, our technicians noticed that the heat pump, although securely mounted on wooden supports, showed signs of prolonged exposure to rain and humidity . These conditions, typical of Montreal flat roofs, can quickly affect electrical boxes and control connections .
Diagnostic steps:
-
Complete visual inspection : we first checked the electrical cut-off box mounted near the condenser.
-
Voltage test : Power was reaching the unit, but the compressor remained inactive.
-
Wiring check : when removing the case cover, we discovered traces of oxidation on the internal connectors.
-
Starter relay test : The relay was partially damaged, probably due to water infiltration .
Solution applied: replacement of the relay and securing of the connections
Once the diagnosis was confirmed, we replaced the faulty relay and carefully cleaned all the connection terminals using an anti-corrosion product.
Then, our technicians have:
-
Checked the wiring continuity to the indoor unit.
-
Tested the compressor and condenser fan.
-
Restored power and observed the complete cycle operation.
Result: The Goodman heat pump restarted without incident, providing stable and quiet cooling from the first few minutes.
Prevention and recommendations
This type of intervention highlights a common problem with roof installations:
Water infiltration and humidity are the worst enemies of the electrical components of a heat pump.
At AirGreen, we systematically recommend:
-
Check the electrical box every spring and fall.
-
To protect the connections using a sealing gasket.
-
Properly raise the units on non-slip supports to avoid direct contact with puddles.
We also advised the building manager to install a rain cover on the box to prevent this type of failure from happening again.
Final result: comfort restored and prevention assured
Within minutes of our intervention, the tenants were back to optimal indoor comfort , despite the humid conditions outside. The Goodman unit, now fully functional, displayed stable refrigerant pressure and excellent energy performance .
This intervention, although simple in appearance, once again demonstrates our expertise in:
-
Rapid diagnosis of electrical faults on roof systems.
-
Preventive maintenance adapted to Montreal's climate.
-
Professional and secure service offered to every client, whether it is a condo, a business or a multi-unit building.
Why choose AirGreen for your heat pump repairs in Montreal and on the North/South Shore?
-
Certified and trained technicians on all major brands: Goodman, Gree, Midea, Fujitsu, Sharp, Lennox, Trane, etc.
-
Fast, priority service in the event of a critical breakdown.
-
Fully equipped vehicles to intervene without delay.
-
Full warranty on all repairs carried out.
At AirGreen, every service call is an opportunity to demonstrate our commitment: restoring comfort, extending equipment life and ensuring peace of mind for our customers .