At AirGreen, we know that installing a ceiling cassette indoor unit is an elegant and high-performance solution for both residential and commercial environments across Montréal, Laval, Longueuil, the North Shore, and the South Shore. However, even seasoned installers can make critical mistakes that compromise the system’s performance and longevity. In this article, we reveal the three most common errors we encounter in the field, with real examples from our service calls—and most importantly, how our experts at AirGreen either prevent or correct them with precision.
A discreet technology, but a demanding one
Ceiling cassettes are popular for their discreet design, uniform 360-degree air distribution, and seamless integration into suspended ceilings. Yet, their installation complexity is often underestimated, leading to errors that can negatively impact energy efficiency, comfort, or even the equipment’s lifespan.
Mistake #1: Poor condensate drainage management
A commonly encountered problem
One of the most frequent errors, even among professionals, involves the routing and slope of the drainage hose. If it’s poorly placed or lacks the necessary incline, condensation water can back up into the unit, causing visible ceiling leaks or, worse, water infiltration into the walls.
Real-life example: Service call in Laval
In a residential building in Laval, a client called us urgently after noticing water stains on the ceiling around a Mitsubishi 18,000 BTU cassette that had recently been installed by another contractor. Upon inspection, our team discovered that a lift pump hadn’t been installed despite a clear elevation difference, and the drain hose was improperly angled.
Our AirGreen solution
Our certified technicians:
-
Reinstalled the drainage system with the proper slope.
-
Added a silent lift pump.
-
Insulated the hose to prevent external condensation.
Since then, the system has worked flawlessly, with no leaks or noise—and the client is fully satisfied.
Mistake #2: Improper sizing for the space
A miscalculation with serious consequences
An overpowered cassette in a small office creates an uncomfortable draft and wastes energy. Conversely, an undersized unit will run constantly under strain, reducing its lifespan and failing to maintain a stable temperature.
Case study in Longueuil
In a dental clinic in Longueuil, a Gree U-Match 24,000 BTU cassette had been installed in a 30 m² treatment room. The result: the compressor was short-cycling, causing unpleasant temperature swings and frequent blowing noises.
What we did
After conducting a thermal analysis of the room and consulting with the client:
-
We replaced the cassette with a Gree 12,000 BTU model, more appropriate for the space.
-
We recalibrated the thermostat and optimized the fan settings.
-
The air is now distributed evenly and quietly throughout the room.
Mistake #3: Poor air distribution setup
The critical importance of placement
Even with a properly sized and installed unit, bad positioning or improper directional fin adjustments can ruin thermal comfort. This often creates hot or cold zones, or unpleasant direct airflow onto occupants.
Example in Montréal
In a Plateau-Mont-Royal loft, a Daikin SkyAir 15,000 BTU cassette was blowing cold air directly onto the living room sofa. The result: constant discomfort, despite the ambient temperature reading as normal. The previous installer had completely overlooked the open-plan layout of the space.
AirGreen’s intervention
We:
-
Reconfigured the directional fins based on the furniture layout and room flow.
-
Slightly relocated the unit to center air distribution across the space.
-
Added a remote temperature sensor for a more accurate ambient reading.
Comfort was fully restored, and electricity use dropped by 12% on average the following month.
Why choose AirGreen for your ceiling cassette needs?
At AirGreen, our expertise in complex HVAC installations is backed by hundreds of completed projects across Montréal, Laval, Longueuil, the North Shore, and the South Shore. Our technicians:
-
Perform precise thermal load analyses before every installation.
-
Optimize airflow distribution for complete comfort.
-
Guarantee installations that meet the highest standards.
We work with the most trusted brands like Mitsubishi, Fujitsu, Gree, LG, Daikin, and provide personalized advice for every project.
Practical tips to avoid these mistakes
For homeowners and building managers
-
Don’t rely solely on BTU ratings: have a full thermal analysis done.
-
Choose a certified installer with ceiling cassette experience.
-
Make sure drainage systems are water-tested before startup.
-
Always request a post-installation configuration report.
Conclusion: AirGreen’s expertise is an invaluable asset
A ceiling cassette is a smart, aesthetic, and high-performance choice—but only if it’s installed with care, precision, and expertise. At AirGreen, we often fix the mistakes of others, but our mission is to prevent them from the start, thanks to our know-how, meticulousness, and commitment to our clients.
For any HVAC project in Montréal, Laval, Longueuil, the North Shore or the South Shore, trust a team known for transparency, execution quality, and exceptional after-sales support.