Installation of a Broan-NuTone HRVH100 air exchanger with HEPA filtration in Terrasse-Vaudreuil, on Île Perrot

What you see when you open the door of an air exchanger, and why almost no one does it

Most owners of an air exchanger have never opened their unit. They know it exists, sometimes hear a faint airflow in the basement, and assume it is working. This is how recovery cores end up clogged with five years' worth of dust, and filters become gray felt that chokes the airflow.

The project we completed in Terrasse-Vaudreuil gives us the opportunity to do the opposite: open the door, identify every component, and explain precisely what the homeowner must do, how often, and above all what they must never do.

The selected unit is a Broan-NuTone HRVH100, a heat recovery ventilator with HEPA filtration, suspended by chains in a finished basement with a suspended ceiling and connected using insulated flexible ducting.

Terrasse-Vaudreuil: small homes, low basements, real constraints

Terrasse-Vaudreuil is one of Quebec's smallest municipalities, wedged between Pincourt and L'Île-Perrot, on narrow lots bordering the river. The housing stock there is distinctive: many homes built between the 1950s and 1970s, several former vacation homes converted into primary residences, and basements whose clearance height was already limited before the addition of a suspended ceiling.

This combination creates three constraints that we regularly encounter on Perrot Island:

• Clearance height. A unit that is too tall simply will not fit beneath the joists once the suspended ceiling has been installed.
• Access for maintenance. An HRV whose door cannot open fully is a unit that is doomed never to be serviced.
• Proximity to the river. Summer humidity is significant there, and finished basements in former cottages leave no room for ventilation mistakes.

The choice of a compact, low-profile unit was therefore not an aesthetic preference, but a feasibility requirement.

The anatomy of an air exchanger, door open

Here is what you find behind the door, from top to bottom.

The heat-recovery core, installed diagonally

This is the centerpiece: a block of thin stacked plates, inserted diagonally into the cabinet. This orientation is not arbitrary. It allows the two airflows—the stale air exiting and the fresh air entering—to pass through the block perpendicularly, each in its own channels, separated by a thin wall.

Heat passes through this wall. Air does not. That is the whole difference between an HRV and a simple air intake: the house recovers the energy without reintroducing the air it has just exhausted.

Diagonal placement also maximizes the exchange surface in a compact cabinet and naturally directs the condensate downward, where it is collected.

Two blowers, two sealed circuits

On either side of the core are two separate fans, each in its own scroll housing. One pushes fresh air into the house, while the other extracts stale air outdoors.

Two motors mean two separately controllable airflows. That is what makes balancing possible, and it also explains why an air exchanger consumes more than a simple exhaust fan—but recovers infinitely more.

The filters and the HEPA stage

Two filter panels frame the core: one on the incoming-air side and one on the outgoing-air side. The second protects the core from indoor dust and textile fibers, a role that is widely underestimated.

The HRVH100 adds a HEPA filtration membrane, capable of capturing 99.97% of particles 0.3 microns and larger. This is the level of filtration that matters to households dealing with seasonal allergies or respiratory problems, and it is what distinguishes this unit from models with MERV-only filtration.

This membrane has its own maintenance schedule, separate from that of the filters: check it every three months and replace it annually. Do not wash it.

The condensate pan and drain

Under the core is a pan that collects the water produced by condensation from stale air in winter. Wipe it with a damp cloth once a year, when cleaning the core. Its drain must remain clear: this is the most frequent and most damaging failure in a neglected HRV.

The insulation and door gasket

The cabinet is lined with a one-piece molded insulator that prevents condensation from forming on the cold walls and dampens blower noise. The door compresses a perimeter gasket all the way around. A door that is not properly closed after maintenance creates a permanent air leak that throws off the system's balance. We emphasize this point with every client to whom we demonstrate the procedure.

The Broan-NuTone HRVH100 at a glance

• Type: heat-recovery ventilator (HRV) with HEPA filtration
• Continuous airflow: 50 to 112 CFM at 0.2 in. w.g. — 50 to 104 CFM at 0.4 in. w.g.
• Apparent sensible efficiency: 75% at 0 °C
• Sensible recovery efficiency (SRE): 65% at 0 °C and 60% at -25 °C
• Fan efficiency: 1.2 CFM/watt
• Filtration: HEPA (99.97% of 0.3-micron particles)
• Connections : 5 inches, on the sides
• Dimensions: 17 × 39 × 12 in (approximately 43.2 × 99.1 × 30.5 cm)
• Weight: 46.5 lb (approximately 21.1 kg)
• Certification : ENERGY STAR
• Warranty: 5 years on parts, limited lifetime warranty on the core

What 65% sensible recovery efficiency is worth in a home on Île Perrot

On a day at 0 °C, fresh air enters the house at approximately 14 °C instead of 0 °C. On a night at -25 °C, it enters at approximately 3 °C. In both cases, no heating element was used to produce this warming: it came entirely from the air the house was about to exhaust outdoors.

However, the compromise must be stated honestly. A HEPA filtration unit has more modest heat-recovery efficiency than a high thermal-performance model because the membrane resists airflow. You choose the HRVH100 for its filtration quality, not for top energy efficiency. Any contractor who promises both at the maximum level in the same unit is not telling you everything.

The suspended ceiling: the main constraint of this project

The available height below the joists once the tiles were installed dictated everything. Three decisions followed.

1. Low-profile design. At 17 inches high, the HRVH100 fits where a 21- or 24-inch unit would have required a soffit in the finished ceiling.
2. Side connections. Top outlets would have required about 30 additional centimeters of vertical clearance for the elbows. Side connections allow the ducts to exit horizontally, aligned with the ceiling cavity.
3. The removable tiles in front of the door. We planned the layout so that removing two tiles would be enough to open the door fully. It is a five-minute detail during design, and a permanent difference for maintenance.

The unit is suspended from the joists by chains, which decouples vibrations from the structure and prevents them from being transmitted to the floor above. The insulated flexible ducts were connected with sealed collars, tensioned and supported, with the vapor barrier resealed with aluminum tape.

Maintenance, step by step

This is the part we systematically show the customer before leaving the job site, with the unit open.

1. Turn off the power. Always do so before opening the door.
2. Remove both filters. Vacuum them to remove accumulated dust, then wash them in a solution of lukewarm water and mild soap. Let them dry completely before reinstalling them. Every three months.
3. Check the HEPA membrane. Inspect it every three months and replace it once a year. Never wash it.
4. Clean the core. Remove it, soak it for at least three hours in a solution of lukewarm water and mild soap, rinse it lightly, let it dry completely, and then reinstall it. Once a year, ideally at the end of summer.
5. Wipe the condensation tray with a damp cloth while the core is removed, and check that the drain flows freely.
6. Inspect both exterior covers. Remove leaves, lint, and insects. In cold weather, make sure no accumulation of snow or ice is blocking the grille.
7. Close the door properly, with the gasket well compressed all the way around.
8. The motors require no maintenance. Do not lubricate them.

What you should never do to the core

• Do not use hot water. Heat deforms the plates and compromises the seal between the two airflows.
• Do not put it in the dishwasher. The combination of heat and harsh detergent will destroy it.
• Do not brush it or clean it with a high-pressure jet. The channels are thin and tear easily.
• Do not reinstall it while damp. Residual moisture promotes mold growth inside the cabinet.
• Do not reinstall it upside down. The installation direction is indicated on the unit.

The mistakes we correct most often

• Installing the unit wherever it fits, without considering access. An HRV wedged above a hot-water tank will never be serviced.
• Washing the HEPA membrane. It is ruined after the very first rinse.
• Forgetting the exhaust-side filter. It protects the core, and it gets clogged just as quickly as the other one.
• Confusing filtration with ventilation. The HEPA membrane cleans the air; airflow is what renews it. Both are necessary.
• Neglecting the drain pan drain. Water ends up on the suspended ceiling, and suspended ceilings do not forgive it.

Regulations and programs

Residential mechanical ventilation in Quebec is governed by the Building Code and the CSA F326 standard, which sets the total required capacity according to the number and type of rooms. New homes certified under Novoclimat require balanced ventilation, for which an HRV is the usual solution.

Financially, an air exchanger is rarely eligible as a standalone piece of equipment. It generally falls under a comprehensive energy assessment, in which the building envelope and ventilation are examined together. Programs change regularly: we validate them with each client at the time of the quote rather than announce an amount that may no longer exist when the contract is signed.

Have your Broan-NuTone air exchanger installed with AirGreen

We design, install, and maintain residential ventilation systems in Terrasse-Vaudreuil, Pincourt, L'Île-Perrot, Notre-Dame-de-l'Île-Perrot, Vaudreuil-Dorion, the West Island, as well as Montreal, Laval, Longueuil, the North Shore, and the South Shore.

One habit sets us apart: we never leave a job site without opening the unit's door in front of the client, removing the core, showing the filters, and explaining the schedule. A homeowner who has seen the inside of their air exchanger once is no longer afraid to open it, and a unit that is opened is a unit that lasts.

For an assessment of your ventilation needs, a quote for HVAC installation, or a HVAC maintenance contract for a Broan-NuTone air exchanger, contact our team. We come to you, take measurements, and explain what you are buying before you buy it.