A technical intervention at height on a Montreal flat roof
At AirGreen , we are regularly called upon to work on installations located in demanding environments. On this day, our team went to the Côte-des-Neiges–Notre-Dame-de-Grâce neighborhood of Montreal for a service call concerning a Daikin wall-mounted heat pump installed on the roof of a residential building. The outdoor unit, although recent, was no longer producing either heating or cooling. The customer reported that the machine shut down shortly after startup, with no apparent error message.
Diagnosis: Identify a loss of efficiency due to a refrigerant leak
Our technician began with a complete visual inspection of the HVAC system . The Daikin outdoor unit was securely mounted on wall brackets, powered by a dedicated cable, and connected via insulated refrigerant pipes. At first glance, nothing unusual was visible: no traces of oil or unusual noise.
However, the symptoms observed (short start, rapid compressor shutdown, no heat) suggested a pressure problem in the refrigeration circuit . Using a double-dial manifold , the technician measured the operating pressures. Result: abnormally low suction pressure , a sign of an R-410A refrigerant leak .
After isolating the sections of the circuit, the leak was located at a slightly cracked flare connection , probably caused by repeated vibration of the wall unit exposed to the wind.
Repair steps: rigor and safety
1. Refrigerant recovery and evacuation
Before any repairs, our team proceeded to completely recover the residual gas using an approved cylinder, complying with environmental standards in force in Quebec. This crucial step prevents any release of harmful fluid into the atmosphere.
2. Repair the fitting and tighten the flanges
The faulty flare fitting was cut and replaced , then properly re-welded according to the manufacturer's recommendations, Daikin. The pipes were then re-insulated to limit heat loss and prevent future vibrations.
3. Evacuating the system
Once the refrigeration line was closed, the technician performed a prolonged vacuum (reaching -30 inHg) to eliminate all traces of moisture and air. This operation ensures the longevity of the compressor and optimal system performance.
4. R-410A refrigerant recharge and final checks
The filling was carried out to the nearest gram , according to the charge indicated on the device's nameplate. Then, pressure and temperature tests confirmed the stability of the circuit. After a few minutes, the heat pump resumed normal operation, delivering a constant temperature and impeccable air flow.
Result: restored performance and satisfied customer
The Daikin heat pump has regained its full efficiency, ensuring the building's indoor comfort. The repair also identified a structural risk: direct wind exposure on the roof. We therefore added anti-vibration silent blocks and recommended an annual preventive check to prevent this type of problem from recurring.
Our client, relieved to have air conditioning back before the rise in summer temperatures, particularly appreciated the speed of intervention and technical transparency of our AirGreen team.
AirGreen Tips for Preventing Refrigerant Leaks on a Wall-Mounted Heat Pump
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Check the supports and anchors : a device subject to vibrations or winds can cause premature wear of the fittings.
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Schedule annual maintenance : A preventative pressure test helps detect minor leaks before they become critical.
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Clean the internal filters regularly : clogging increases the load on the compressor and accelerates the deterioration of the circuit.
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Use certified technicians : Handling refrigerants like R-410A requires skills and recognized environmental certification.
Why choose AirGreen for your heat pump repair in Montreal?
Our team of specialized HVAC repair technicians in Montreal, Laval, Longueuil, the North Shore, and the South Shore provide fast, professional service that meets the highest industry standards. With our experience working with major brands like Daikin, Fujitsu, Gree, Midea, Sharp, and Goodman , we guarantee long-lasting service and optimal comfort, both summer and winter.