A service call for a wall unit that was no longer blowing hot air
At AirGreen , we frequently intervene in Candiac , on the South Shore, for problems with Fujitsu wall-mounted heat pumps that are losing performance. That day, our client contacted us after noticing that the indoor unit was no longer producing heat , although the outdoor compressor seemed to be operating normally. A typical case where a thorough diagnosis was required.
First observation: filters and coil completely clogged
Upon arrival, we immediately removed the top cover from the wall unit.
The air filters were saturated with dust and fibers , preventing airflow through the evaporator coil.
The tangential fan (the interior turbine) was running at idle, causing very little airflow and almost no heat coming out of the flaps.
Upon closer inspection, we also noticed a slight buildup of ice on the inner coil , a sign of pressure imbalance in the refrigeration circuit due to restricted airflow.
Technical diagnosis: lack of maintenance and automatic protection activated
After checking the system temperatures and pressures, our technicians confirmed that the unit went into protection mode after a few minutes of operation.
The evaporator temperature sensor detected excessive cooling, shutting off the compressor to prevent damage.
The main causes identified:
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Clogged filters;
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Clogged evaporator coil;
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Inner turbine unbalanced due to dust accumulation;
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Partially blocked condensate drain.
This type of situation, while common, can quickly lead to more serious failures if the unit continues to operate under these conditions—including premature compressor wear or refrigerant leakage.
AirGreen Intervention: Deep Cleaning and System Reset
Our experts undertook a complete restoration intervention , including:
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Complete disassembly of the front panel and removal of the air filters ;
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Antibacterial washing of filters and disinfection of the coil with a specialized cleaner;
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High precision cleaning of the turbine to remove fine particles accumulated on the blades;
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Defrosting the coil using a flow of tempered air;
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Purging the condensate drain to ensure proper water drainage;
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Reset sensors and full performance test after reboot.
Results: restored performance and comfort regained
After the interview, measurements showed a blown air temperature of 47°C in heating mode , compared to only 26°C before our arrival.
The compressor discharge pressure has stabilized, and the airflow has returned to normal.
The client immediately noticed a reduction in noise and a noticeable improvement in thermal comfort in the main room.
We have also taken care to explain good maintenance practices, including:
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Clean the filters every 2 to 3 months;
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Have an annual professional cleaning carried out before the cold season;
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Check drainage to prevent water leaks.
AirGreen: Certified HVAC experts on the South Shore and in Montreal
This intervention in Candiac clearly illustrates the importance of preventive maintenance of Fujitsu wall-mounted HVAC systems .
At AirGreen , we prioritize precise, efficient and long-lasting interventions, carried out by certified technicians trained on all major brands: Fujitsu, Midea, Gree, Lennox, Sharp, Zephyr, Trane and many others.
Our services cover Montreal, Laval, Longueuil, the North Shore and the South Shore , for all types of intervention:
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Repair of wall-mounted or central heat pumps;
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Complete maintenance and antibacterial cleaning;
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Performance diagnosis and energy optimization.
Each AirGreen visit has a single goal: to restore comfort, extend the life of your equipment and maximize its performance.
In conclusion
Thanks to rapid intervention and comprehensive maintenance, this Fujitsu heat pump in Candiac is now operating at full capacity.
A simple clog can be enough to compromise an entire system, but with regular AirGreen monitoring, your comfort remains constant and your investment protected .