A compressor stopped: rapid diagnosis and repair by AirGreen
At AirGreen , we regularly intervene to resolve breakdowns of Fujitsu wall-mounted heat pumps , renowned for their reliability, but which, like any HVAC system, require rigorous maintenance. In Sainte-Julie , a customer contacted us about a Fujitsu outdoor unit that was no longer starting, despite an active heating control on the indoor unit.
Symptoms reported by the client
The client noted:
-
Failure of the outdoor fan to start ;
-
No compressor noise when starting the cycle;
-
A flashing light on the indoor unit indicating a communication error.
These clues suggested an electrical or electronic problem , possibly related to the power supply or the compressor control board.
Visual inspection and initial checks
On site, our certified technician first performed a complete visual inspection of the outdoor unit. The Fujitsu compressor, although protected under a shelter, showed signs of wear and dust accumulation on the heat exchange grid. A quick multimeter test on the disconnect block revealed no output voltage , despite a correct input power supply.
This observation pointed to a failure of the external circuit breaker , an element often overlooked but essential to the proper functioning of the system.
Steps of repair
-
Safe disconnection of the main power supply to avoid any electrical risk.
-
Opened the disconnect box : the internal thermal fuse showed wear and slight blackening.
-
Replacement of the complete housing with a sealed CSA compliant model , ensuring better weather resistance.
-
Cleaning the outdoor condenser with compressed air to clear the fins clogged with dust and debris.
-
System restart and load test : the compressor restarted immediately, with stable amperage and within Fujitsu specifications.
Diagnosis confirmed and results obtained
The fault was therefore caused by a failure of the cut-off box , preventing the outdoor unit from receiving the current necessary to start the compressor and the fan. After replacing and checking the connections, the heat pump resumed normal operation.
The results were immediate:
-
Smooth restart of the compressor after power-up;
-
Stable and powerful hot air emission inside;
-
Silent operation restored thanks to the complete overhaul of the outdoor module.
Maintenance advice given to the customer
To avoid this type of breakdown, our AirGreen experts recommended:
-
A biannual visual inspection of the exterior electrical box;
-
Annual cleaning of the condenser to prevent overheating and poor electrical contacts;
-
Installing a winter protective cover to prevent moisture and ice buildup in the cut-off box.
These simple actions not only extend the life of the heat pump, but also preserve its energy efficiency throughout the year.
Why choose AirGreen for your Fujitsu repairs?
As an authorized Fujitsu dealer and installer in Greater Montreal, AirGreen has the expertise and certified parts for every wall-mounted heat pump model. Our technicians use advanced diagnostic tools and adhere to manufacturer service protocols, guaranteeing:
-
Safe and durable repairs ;
-
Original parts adapted to each series;
-
Rapid intervention in all regions of Montreal, Laval, Longueuil, the North Shore and the South Shore.
An intervention that restores confidence
The Sainte-Julie client regained the comfort of his home in less than two hours, impressed by the accuracy of the diagnosis and the clarity of our explanations. As is often the case in our interventions, the key lies in a methodical verification of each link in the HVAC electrical circuit .
This repair perfectly illustrates the AirGreen philosophy: precision, transparency and performance in the service of residential comfort .