Costly mistakes to avoid: real lessons from the field by AirGreen
Summers in Montréal are unforgiving when it comes to commercial air conditioning missteps. Every year, too many businesses face avoidable breakdowns, sky-high energy bills, or ongoing discomfort for their employees and clients. At AirGreen, we’re regularly called into situations that have become critical—situations where poor planning or neglected maintenance end up costing a fortune. In this article, we reveal the 5 most common mistakes we see in shops, offices, and industrial spaces across Montréal, Laval, Longueuil, as well as the North Shore and South Shore. Better yet: we’ll show you how to effectively avoid them.
Mistake #1: Underestimating your building’s actual cooling load
One of the most damaging mistakes in commercial AC installation is choosing a system that’s incorrectly sized. Too often, businesses rely solely on square footage, without accounting for the building’s specific thermal load—sun exposure, occupancy levels, number of electronic devices, or poor insulation.
Real-world example in Montréal:
We recently replaced a 60,000 BTU unit in a small print shop in Rosemont. The previous contractor had poorly assessed the heat load, completely ignoring the heat generated by the industrial printers. The result: the building overheated every summer, productivity dropped, and the compressor wore out prematurely.
Our tips:
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Always perform a complete thermal load calculation (CSA-F280 method).
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Choose a commercial heat pump or multi-zone wall-mounted AC that suits your operations.
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Stick with proven brands like Fujitsu, Daikin, Lennox, or Gree, known for reliable performance in commercial settings.
Mistake #2: Neglecting regular HVAC maintenance
Lack of maintenance is another major cause of summer headaches. Dirty filters, blocked coils, or incorrect refrigerant levels can reduce your AC system’s efficiency by over 30%. That not only leads to higher energy bills but also results in less comfort indoors.
Case study in Longueuil:
At a medical office, our team found mold buildup in the ductwork, all because preventive maintenance had been ignored. It impacted indoor air quality and created a health hazard. After a full cleaning, the air quality improved significantly, and the unit regained 20% of its performance.
Our tips:
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Set up an annual HVAC maintenance plan with scheduled preventive visits.
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Include static pressure testing, condensate inspection, and sensor checks.
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Go for a commercial maintenance contract with AirGreen, tailored to your sector (healthcare, food service, offices, etc.).
Mistake #3: Overlooking grants and incentive programs
Every summer, we meet business owners who have invested in a new HVAC system without knowing they were eligible for substantial financial incentives. In Montréal and surrounding regions, Hydro-Québec and other municipal programs offer rebates for replacing outdated systems with more efficient heat pumps.
Installation in Laval:
A hair salon in Chomedey recently chose a Bosch BOVA 5-ton central heat pump, which qualified for a $3,850 rebate under the LogisVert program. That amount covered a large portion of the upfront cost.
Our tips:
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Before any installation, we run a full energy cost-benefit analysis, including available grants.
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Look into ENERGY STAR certified heat pumps and systems using R-32 or R-454B refrigerants.
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Ask AirGreen for a free eligibility evaluation for rebate programs.
Mistake #4: Failing to plan for redundancy in critical installations
In businesses or institutions where consistent indoor temperatures are essential (clinics, server rooms, labs), not installing backup systems is a strategic mistake. One failure can lead to serious losses.
Case from the South Shore:
A pharmaceutical company in Boucherville experienced a 48-hour production halt due to their only AC unit failing. After this incident, we installed a redundant backup system with automatic switchover, ensuring seamless operation during any future outage.
Our tips:
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In sensitive environments, include a dual HVAC system, even if the backup is partial.
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Set up an emergency power supply for critical HVAC equipment.
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AirGreen designs custom commercial air conditioning systems with smart redundancy features.
Mistake #5: Hiring a non-specialized HVAC installer
Lastly, the most expensive mistake is hiring a general contractor instead of a licensed commercial HVAC specialist. Commercial systems require expert knowledge of ventilation, zoning, smart controls, and safety standards.
Intervention on the North Shore:
A sports center in Blainville had a VRF system installed without proper integration into the building’s automation controls. The result: excessive energy use and constant discomfort. AirGreen had to reconfigure everything, reprogram thermostats, and optimize the airflow throughout the facility.
Our tips:
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Choose a licensed HVAC contractor (RBQ-certified) with commercial building experience.
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Ask for detailed references in your specific industry.
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AirGreen brings over 15 years of expertise in complex commercial HVAC installations in Montréal and surrounding areas.
Conclusion: Leave your commercial comfort to the experts
Every summer, avoidable mistakes end up draining businesses’ performance and budgets across the Montréal region. At AirGreen, we’ve built our reputation by fixing those mistakes, educating our clients, and delivering reliable, long-lasting, and grant-eligible commercial HVAC systems.
Whether you’re looking for a new wall-mounted heat pump, a central system, or a complete equipment maintenance plan, we’ll guide you from needs assessment to post-sale service, including assistance in securing available rebates.
Contact us today for a free diagnostic and a custom proposal that fits your commercial needs.