A simple inspection. An alarming discovery.
In the heart of Longueuil, inside a three-story office building, our AirGreen team was called in for what initially seemed like a routine inspection. What we uncovered turned out to be a textbook example of how HVAC installation errors — often invisible — can severely impact energy performance and workplace comfort. An estimated annual energy loss of over $15,000 was on the line.
Context: a minor complaint... hiding a major issue
The building manager contacted us after receiving recurring complaints from employees: cold spots on the ground floor, stifling heat on the third floor, and a constant sense of poor air circulation — especially during heating season. The building had been renovated three years earlier, with the installation of a central HVAC system from a well-known brand, supposedly designed to meet all the building’s needs.
Yet despite the system being fairly new, the problems persisted.
AirGreen’s Diagnosis: a combination of several critical mistakes
From our very first audit, several obvious signs of misconfiguration became clear:
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Oversized main system: A 10-ton central heat pump that was far too powerful for the building’s actual needs. The result? Frequent starts and stops, increased consumption, and premature wear.
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No duct balancing: Air was being pushed at full force into some areas, while others remained underserved.
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Thermostats poorly positioned: Installed near heat sources (large south-facing windows), skewing temperature readings.
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Faulty motorized damper: One of the zone damper motors hadn’t opened in months, severely limiting fresh air to a floor housing 22 employees.
With our thermal imaging and static pressure tools, we were able to precisely map the system’s imbalances.
Tangible consequences: degraded comfort and significant financial loss
The lack of balancing and incorrect system sizing had direct consequences:
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Uneven thermal comfort: More than 30% of the offices were either too hot or too cold.
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Excessive energy use: The short cycling of the heat pump led to 22% higher consumption than expected for a similar-sized building.
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Higher maintenance costs: Several system components were suffering from erratic operation, particularly the main compressor and blower fans.
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Productivity impact: According to the building manager, absenteeism had slightly increased, and HR complaints had been piling up for months.
Our calculations estimated that these issues were causing over $15,000 in annual energy and operational losses.
AirGreen’s Solution: correct, optimize, and educate
At AirGreen, we believe every problem is an opportunity to optimize. Here’s how we turned things around:
1. Complete balancing of the duct network
Using an anemometer and airflow sensors, we adjusted each diffuser to ensure even air distribution across all three floors. This reduced temperature variations from over 5°C down to less than 1°C.
2. Replacement of the faulty motorized damper
We installed a new programmable motorized damper with real-time smart home monitoring, ensuring optimal regulation even when staff are offsite.
3. Strategic repositioning of thermostats
We relocated the thermostats to neutral zones, away from windows and heat-generating appliances. Then we fine-tuned calibration for better synchronization with system cycles.
4. Optimized programming of the heat pump
By reprogramming the cycles and adding a compatible Inverter regulation module, we eliminated the frequent short cycling — resulting in 17% energy savings in the first month alone.
5. Quick training session for building maintenance staff
Finally, we delivered a 2-hour training session to the building’s technical manager covering best practices for HVAC system maintenance.
Results: immediate and long-term improvement
One month after our intervention, the benefits were already measurable:
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19% drop in energy bills compared to the same period the year before.
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Zero complaints about temperature inconsistencies.
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Improved comfort throughout the offices and higher staff satisfaction.
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Extended expected lifespan of the heat pump, now operating in stable cycles.
What this intervention teaches us
Even the best equipment — whether it’s a central heat pump from Goodman, Zephyr, or Midea, or a Lennox VRF system — can fail without precise installation and proper configuration. This Longueuil case clearly shows the importance of:
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Accurate system sizing
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Expert ductwork balancing
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Ongoing training for facility managers
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And a competent, committed HVAC partner like AirGreen
Managing a commercial building in Longueuil, Laval, or Montréal?
If you suspect excessive energy use or your staff complains about indoor comfort, contact AirGreen for a full system evaluation. Our audits may uncover hidden savings — just like they did here.