An accurate diagnosis in a downtown Montreal apartment
During a service call in Côte-des-Neiges–Notre-Dame-de-Grâce, our AirGreen team was contacted by a customer who was experiencing insufficient cooling with their Fujitsu wall-mounted air conditioner . Despite the indoor unit seemingly operating normally, the ambient temperature remained high and the blown air was not sufficiently cool.
Located in a renovated older apartment, the Fujitsu wall unit—installed for about eight years—was showing typical signs of neglected maintenance and degraded performance . The client wanted to avoid a complete breakdown before the summer, a wise preventative approach that we strongly encourage.
Complete inspection and root cause analysis
Upon arrival, we performed a complete visual and functional diagnosis . The indoor unit appeared clean, but a closer inspection revealed:
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A partially clogged air filter , reducing airflow.
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Evaporator fins clogged with dust and ambient microfibers.
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Slow condensate flow , caused by a slight obstruction in the drainage pipe.
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A slight drop in refrigerant pressure , possibly due to a micro-leak in the fittings.
Analysis of the refrigeration circuit pressures confirmed a refrigerant charge lower than the Fujitsu manufacturer's standard. This explained the air conditioner's reduced efficiency.
Technical intervention: cleaning, resealing and recharging
Our certified technicians undertook a complete maintenance and upgrade procedure . Following the power outage, the unit was partially disassembled to allow for a thorough cleaning of:
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The evaporator, with a specialized biodegradable product.
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The tangential fan, often overlooked, but essential for good airflow.
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The condensate tray and the drainage pipe.
Next, the refrigeration circuit was tested with nitrogen to detect any leaks. A micro-leak was located on the service valve connection, which we re-brazed and re-sealed before carrying out a complete vacuum . Finally, we recharged the circuit with R410A refrigerant , respecting Fujitsu's exact specifications.
Performance verification and results
Once the unit was restarted, we measured the supply air temperature: a difference of more than 13°C between the ambient air and the supply air, indicating optimal performance. The compressor was running quietly, the fan was blowing at full capacity, and the circuit pressure was stable.
The customer immediately noticed the improvement: the room cooled down quickly, and the air conditioner resumed a normal operating cycle without excessive effort.
Preventive maintenance recommendations
At AirGreen, we emphasize the importance of complete annual maintenance for any wall-mounted air conditioning system, especially in urban areas like Montreal and Laval where indoor dust and temperature fluctuations are significant. To prevent breakdowns and maintain peak performance, we recommend:
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Cleaning the filters every 4 to 6 weeks during the summer season.
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An annual professional inspection including pressure measurement and coil cleaning.
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Checking drainage to avoid water overflow.
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Use ventilation mode periodically to avoid humidity stagnation.
Our RBQ and CCQ certified technicians are trained to maintain and repair all major brands, including Fujitsu, Sharp, Gree, Midea, Bosch and Lennox . Every AirGreen intervention aims to extend the life of the device and ensure consistent comfort , summer and winter.
AirGreen: Your Trusted HVAC Partner in Montreal
A simple performance drop can mask a serious problem. Thanks to our technical expertise and rigorous approach, we ensure precise, fast, and lasting repairs throughout Greater Montreal, Laval, Longueuil, the North Shore, and the South Shore.
AirGreen – Repair, maintenance and optimization of Fujitsu wall-mounted air conditioners.