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Révélations d’expert : Ce que votre entrepreneur en ventilation ne vous dira jamais
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Expert Revelations: What Your Ventilation Contractor Will Never Tell You

When lack of transparency can harm your family’s health and your HVAC system’s performance

At AirGreen, we’re often called in after another ventilation contractor has installed an air exchanger or HVAC system that’s either unsuitable, poorly configured, or even dangerous. Too often, homeowners contact us after experiencing poor air quality, abnormally high energy bills, or insufficient thermal comfort. Why? Because some contractors don’t tell you everything. Here are the truths that we, as specialists in residential and commercial ventilation in Montréal, Laval, Longueuil, North Shore, and South Shore, believe you deserve to know.

1. Not all air exchangers are equal—even if they’re “certified”

Many contractors recommend “standard” units without taking the time to assess the building layout, existing humidity levels, or actual airflow requirements. An undersized or poorly placed air exchanger won’t provide full air renewal, even if it looks compliant on paper.

Real example: in Longueuil, a couple had a contractor install an HRV system. The result: indoor humidity stayed above 70%, mold appeared in the bedrooms, and the children developed chronic rhinitis. We replaced the unit with a Venmar EVO5 500 HRV, calibrated to their square footage and real occupancy. Humidity dropped to 45% within a week.

2. Ventilation ducts need to be cleaned—even if they’re brand new

A persistent myth: new systems don’t need cleaning. False. Construction and renovation work leaves behind fine dust, gypsum residue, or mineral wool particles inside the ducts. If the contractor doesn’t thoroughly clean the system before first use, you’ll be breathing that mix from day one.

At AirGreen, every installation includes a full visual inspection of the ductwork and high-pressure dust removal if needed. This is a step many contractors skip to save time.

3. The position of the air exchanger changes everything

Installing an HRV in a basement corner without considering airflow paths, physical obstructions, and ventilation zones is a common mistake. Poor placement causes:

  • Dead zones where air doesn’t circulate (e.g., bedrooms or upper floors).

  • Excessive noise in some rooms.

  • Uncomfortable drafts near vents.

Concrete case: in Montréal-Nord, a client had a high-pitched noise in their bedroom. The HRV was mounted on a steel beam with no acoustic suspension. We reinstalled it on vibration-dampening mounts and added duct silencers: the noise disappeared.

4. Many contractors ignore available subsidies

We’ve seen clients pay $1,200 to $2,000 more than necessary just because their contractor never mentioned the available grant programs. As of today, several subsidies are available for energy-efficient systems like HRVs:

  • LogisVert (Hydro-Québec): up to $850 reimbursed for an HVI-certified exchanger.

  • RénoClimat: applicable for energy-efficient renovation projects.

  • Municipal programs (e.g., Montréal, Laval, certain North Shore MRCs).

AirGreen handles it all: eligible model selection, help filling out the forms, and documentation of energy performance.

5. Some installed units are already outdated

Yes, some contractors are still selling discontinued models or units that no longer meet 2023 HVI standards. These systems:

  • Are noisy.

  • Offer poor thermal recovery efficiency.

  • Are ineligible for subsidies.

  • Use more energy than newer models.

We were recently called to a job in Sainte-Thérèse where a “brand-new” air exchanger installed 6 months earlier had a spec sheet dated 2015. We replaced it with a Lifebreath 155 MAX, reducing annual electricity consumption by 27%.

What AirGreen does differently

We believe technical transparency is essential. That’s why:

  • We conduct a full site analysis before recommending anything.

  • We only propose recent, certified, efficient, and quiet equipment.

  • We detail every step, every cost, and every benefit of the installation.

  • We tailor the solution to your real lifestyle needs: number of occupants, daily habits, pets, etc.

  • We provide post-installation follow-up, including airflow checks, humidity testing, and training on how to use the system.

Why trust AirGreen

  • 1,200 successful installations in Montréal, Laval, Longueuil, North Shore, and South Shore.

  • Specialized technicians in residential and institutional ventilation.

  • High-quality equipment: Venmar, Lifebreath, Fantech, Aldes.

  • Full support, from initial evaluation to grant applications.

  • Fast, friendly, meticulous service, always tailored to your reality.

Conclusion: What you need to remember

What some contractors won’t tell you, AirGreen explains from day one, with honesty and precision. Installing a ventilation system should never be a rushed or price-driven decision. It deserves a rigorous, customized, and truly professional approach.

Looking for a reliable, long-lasting, high-performance installation? Contact us for a free evaluation of your ventilation system.