A service call for a unit blowing warm air
At AirGreen , we were contacted by a customer in the Côte-des-Neiges–Notre-Dame-de-Grâce neighborhood of Montreal , who was concerned that their Sharp wall-mounted heat pump was no longer producing cold air. During a heatwave, the wall-mounted unit, renowned for its reliability, was blowing lukewarm air, making the main room uncomfortable.
Our mission: to quickly diagnose the fault, identify the cause, and restore the performance of the HVAC system without delay.
Initial inspection: a clean but inactive unit
Upon arrival, we conducted a thorough visual inspection. The Sharp appliance, well maintained and installed at the correct height in the living room, showed no apparent signs of leaks or obstructions.
However, upon startup, we noticed:
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Low airflow , even at maximum speed.
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No temperature difference between the blown air and the ambient temperature.
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An intermittent noise from the outdoor compressor , suggesting a communication failure or pressure problem.
These clues pointed us towards a problem with the refrigeration cycle or the control board .
In-depth diagnosis: checking the refrigeration circuit
Our technician then inspected the outdoor unit paired with the wall-mounted heat pump. After connecting our pressure gauges, the measurements indicated:
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Abnormal low pressure , typical of a partial lack of refrigerant .
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No visible signs of leaks at the fittings, but a slight oily residue near the vacuum hose flare.
We therefore applied a leak detection test using an electronic detector with a heated sensor , which confirmed the presence of a microleak at the expansion fitting .
Next step: repairing the refrigeration circuit
In order to correct the situation, our team has undertaken the following actions:
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Complete recovery of the remaining refrigerant in the system to avoid any emissions.
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Disassembly and cleaning of the flare fitting , followed by replacement of the seal .
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Reinforcement weld on the main fitting to prevent future vibration.
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Nitrogen pressure test for 20 minutes to ensure no residual leaks.
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Complete vacuum (500 microns) before recharging.
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Recharge the system with R-410A refrigerant , according to the charge indicated by Sharp.
Once the charge was completed, the heat pump was restarted: the compressor started normally , and the air leaving the wall unit dropped to 9°C , optimal efficiency.
Additional step: cleaning and calibration
To maximize performance after repair, we have:
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Cleaned the air filters and evaporator coil .
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Checked communication between indoor and outdoor boards .
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Calibrated the built-in ambient temperature sensor .
These adjustments restored temperature control accuracy and system responsiveness, ensuring consistent comfort.
Result: restored comfort and optimized efficiency
After our interventions:
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The unit blew constant, steady cold air.
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Electricity consumption has returned to normal.
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The noise level has stabilized thanks to the reduction of abnormal cycles.
The client immediately noticed the difference and was impressed by the speed of the restoration. In less than two hours, his living room was fresh and pleasant again.
Prevention and maintenance advice
We recommended a few simple steps to the customer to preserve the longevity of their Sharp heat pump:
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Clean the filters every month during the summer.
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Check the operating lights on the remote control or wall unit.
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Schedule annual preventative maintenance including checking the refrigerant, drain and electrical connections.
An undetected microleak can reduce system efficiency by up to 30% and, in the long term, damage the compressor. A simple annual inspection can prevent this type of failure.
Why choose AirGreen for your Sharp heat pump repairs?
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Certified technicians specializing in Sharp, Fujitsu, Midea, Gree and other leading brands.
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Rapid intervention throughout Greater Montreal: Montreal, Laval, Longueuil, North Shore and South Shore .
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Original parts and methods approved by manufacturers.
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Guarantee on all repairs , ensuring customer peace of mind.
At AirGreen , every service call is handled with rigor and attention to detail, so that your HVAC system returns to full efficiency — sustainably.
Conclusion: precision service in Côte-des-Neiges
This intervention on a Sharp wall-mounted heat pump in Côte-des-Neiges–Notre-Dame-de-Grâce perfectly illustrates our approach: precise diagnosis, reliable repair, restored performance .
With our HVAC expertise, we bring your heating and air conditioning systems back to life with professionalism, efficiency and courtesy.