Fast and careful intervention on a Lennox heat pump installed on a flat roof
At AirGreen , we are often called upon to work in complex urban environments, where accessing and installing HVAC systems requires specific technical expertise. This was the case during this repair of a Lennox wall-mounted heat pump located on the flat roof of a residential building in the Ville-Marie district of Montreal .
The outdoor unit, exposed to the sun and the elements, had recently stopped working properly, causing a lack of air conditioning inside the apartments.
Diagnosis: A problem of condensation and excessive vibration
When our team arrived on site, we first conducted a complete inspection of the Lennox system .
The symptoms observed by the client were:
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A loud vibrating noise on the roof;
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A noticeable drop in performance in cooling mode;
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Irregular compressor start-up.
After several tests, our technician quickly identified two main causes:
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Unstable fixing of the outdoor unit support , causing abnormal vibrations amplified by the roof structure.
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Moisture buildup in the condensation drain , causing partial water backflow and occasional overheating of the compressor.
Repair carried out: stabilization, cleaning and optimization
Once the diagnosis was confirmed, we undertook several specific corrective actions:
Mechanical stabilization
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Complete repositioning of the aluminum support on the wooden side members to ensure perfect weight distribution.
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Added industrial-grade anti-vibration pads to eliminate resonances from the roof.
Cleaning and unblocking the drainage system
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Disassembly and complete cleaning of the condensation pipe , blocked by dust and gravel residue.
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Check the drainage slope to ensure free flow of water.
Electrical and functional verification
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Complete test of the Lennox compressor and control board .
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Control of refrigerant pressure and blowing temperature.
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Validation of communication between the indoor and outdoor unit.
After these interventions, the Lennox heat pump resumed normal operation: the compressor started up smoothly and quietly, and the customer immediately felt a rapid return of thermal comfort in the rooms served.
AirGreen Expertise: reliability at the heart of every service
This type of intervention perfectly illustrates our approach:
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Rigorous analysis before any repair ,
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Compliance with safety standards for exposed roofs and systems,
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Use of Lennox certified parts and professional tools adapted to each situation.
Our technicians are trained to work in all possible configurations—whether it's typical flat roofs in downtown Montreal , single-family homes in Laval, or condominium buildings on the South Shore.
Result: a quieter and more durable Lennox system
Thanks to the AirGreen intervention:
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Vibrations have been eliminated 100% ;
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The airflow has returned to its original power;
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The system is now operating at full energy efficiency ;
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The customer once again enjoys constant comfort and stable air conditioning.
We also advised the owner to perform biannual preventative maintenance to prevent drain clogging and extend the life of the compressor.
In conclusion
This Lennox wall-mounted heat pump repair in Ville-Marie demonstrates how precision and experience make all the difference.
At AirGreen, every service call is treated with the same care, whether it's a simple suspicious noise or a complete breakdown.
We offer professional HVAC services in Montreal, Laval, Longueuil, on the North Shore and the South Shore , always with a constant concern for quality, durability and energy performance.
AirGreen – Experts in HVAC systems Lennox, Midea, Fujitsu, Gree, Goodman and more.