Installation of a Broan-NuTone HRV160 ECM heat recovery ventilator in Sainte-Martine, Montérégie

When a well-sealed house stops breathing: the Sainte-Martine project

A 1,850 sq. ft. bungalow with three bedrooms, built in the early 2010s in a residential development in Sainte-Martine, along the Châteauguay River. A tight envelope, triple-glazed windows, and spray foam in the crawl space. On paper, an energy-efficiency success. In reality, the owners called us in February because the living-room windows streamed with water every morning, the main bathroom took more than two hours to dry after a shower, and a blackish ring kept reappearing in the silicone joint behind the bathtub.

The diagnosis did not take long. The house had a basic bathroom fan and nothing else. No controlled fresh-air supply, no heat recovery. Indoor relative humidity fluctuated between 62% and 68% in the middle of winter, while the recognized target is between 40% and 60%. At AirGreen, we offer complete HVAC solutions throughout the South Shore, and this type of call represents a growing share of our projects in Montérégie: these are no longer old homes lacking insulation, but new homes lacking air.

Why choose an HRV rather than an ERV in Sainte-Martine

The distinction is simple, but it is poorly explained in most of the quotes our clients show us.

• An HRV (heat recovery ventilator) transfers only heat between stale outgoing air and fresh incoming air. It exhausts excess moisture outdoors.
• An ERV (energy recovery ventilator) transfers both heat and some moisture, which limits drying in winter and moisture intake in summer.

In a home where the main problem is excess winter humidity—condensation, mold, fogged-up windows—an HRV is the right tool. An ERV would have retained some of that moisture indoors, exactly what needed to be avoided. We recommend ERVs more often for overheated condos in central Montreal, where the air becomes too dry in January, or in certain homes on the North Shore occupied by few people. In Sainte-Martine, with four occupants, two daily showers, and frequent cooking, the calculation clearly favored an HRV.

The unit we chose: Broan-NuTone HRV160 ECM (HRV160TE)

We selected the Broan-NuTone HRV160 ECM, model number HRV160TE, from the HE series.

The figures that really matter

The most important figure in this table is not 83%. It is the 64% sensible recovery efficiency at −25 °C. Many manufacturers proudly publish their efficiency at 0 °C while remaining discreet about performance in extreme cold, because that is when ordinary cores lose effectiveness and defrost cycles become longer. In Sainte-Martine, where we have recorded mornings as cold as −27 °C, a unit that retains nearly two-thirds of its recovery under these conditions has a tangible impact on the Hydro-Québec bill.

The ECM motor: the real recurring savings

The HRV160 ECM uses electronically commutated motors. Compared with standard motors, they reduce electricity consumption by approximately 67% on average. An air exchanger operates 8,760 hours per year. This difference is not apparent on the day of installation, but it adds up over fifteen years.

The MERV 9 also deserves mention. It is a significantly higher level of filtration than the MERV 6 offered on several competing units in the same range, and it captures a substantial amount of pollen and fine dust—an important advantage in Sainte-Martine, surrounded by farmland where plowing and harvesting periods load the air with particles.

The VT8W wall control and the VB60W boost switch

A detail that few homeowners know: the HRV160 ECM is not compatible with entry-level wall controls. Unlike the VT4W or VT6W models, which work with simpler units, this appliance requires a VT8W or VT9W main control.

We installed a VT8W in the hallway near the mechanical closet door. It provides access to the built-in dehumidistat, intermittent mode (20 minutes per hour), recirculation, smart mode, and independent adjustment of the continuous minimum and maximum speeds. This control manages the home's whole-house ventilation strategy.

The small “VENTILATION” plate in the bathroom

The project photo shows the other half of the system: a Broan VB60W boost switch, installed in the primary bathroom on the glass mosaic wall.

It is a 20-, 40-, or 60-minute timed boost. Pressing the bottom of the rocker switch puts the air exchanger into high speed for the selected duration, after which the unit automatically returns to its normal setting. The three LEDs indicate the active setting.

We emphasized three points during installation:

1. Location. Outside the shower splash zone, approximately 1,200 mm above the floor, on the wall next to the door. A control placed too far away is never useful.
2. Cutting the glass mosaic. This is the delicate part. The tile was already in place, and the client categorically refused a damaged grout border. We cut it with a wet saw and a diamond blade for glass, working from the back of the wall to prevent the glass face from chipping, then adjusted the depth of the electrical box so the plate would sit perfectly flush without putting pressure on the tile. A plate screwed too tightly onto glass will always end up cracking it.
3. Low-voltage wiring. The boost switch operates at low voltage and must never share a conduit with 120 V. We ran a dedicated cable to the unit.

The result is what you see in the photo: a discreet control, aligned with the mosaic layout, with the word VENTILATION engraved on the plate. Nothing that looks out of place in a renovated bathroom.

The project timeline, and the mistakes we see everywhere

Two days, a 32-inch mechanical closet

Day 1 — Ductwork. Suspending the unit on vibration isolators from the joist of the finished basement, never rigidly fastening it to the wood: this is the leading cause of vibration transmission in a single-story home. Drilling the two wall penetrations and installing the exterior caps more than six feet apart to prevent exhaust air from being drawn back into the fresh-air intake. Routing exhaust ducts to the primary bathroom, powder room, and laundry room; fresh-air supply ducts to the three bedrooms and living room.

Day 2 — Insulation, drain, controls, and balancing. The two ducts connecting the unit to the outdoors were insulated with a sealed vapor barrier along their entire length. The condensate drain was connected with a trap and continuous slope toward the floor drain. Installation of the VT8W and VB60W. Then balancing.

The three most common mistakes we correct in other people's installations

• Uninsulated or poorly sealed outdoor ducts. In January, an uninsulated fresh-air duct becomes covered in condensation, water runs into the ceiling insulation, and two years later it becomes an insurance claim. We have corrected several such installations in Châteauguay and Mercier.
• Outdoor intakes and exhaust outlets too close together. The unit then draws in its own stale air again, and its efficiency plummets without anyone understanding why.
• No balancing. This is the most common and costly mistake.

Balancing the airflow: the step too many installers skip

An unbalanced air exchanger puts the home under positive or negative pressure. Under negative pressure, the home draws air through cracks, the crawl space, and sometimes through the vent pipe of a combustion appliance. Under positive pressure, humid indoor air is pushed into the walls, where it condenses.

We measured the supply and exhaust airflow rates at the pressure taps on the unit's access door, adjusted them until the difference between the two was less than 10%, and then documented the final values on a label affixed to the cabinet. The customer leaves with verifiable data, not a promise.

Sizing it correctly: the calculation, plainly explained

The method recognized by ASHRAE 62.2-2010 is as follows:

CFM = 0.01 × area (sq. ft.) + 7.5 × (number of bedrooms + 1)

For this Sainte-Martine home: 0.01 × 1,850 = 18.5, plus 7.5 × 4 = 30, for a total of 48.5 CFM of continuous ventilation. The flat-rate table in the same standard would have required 60 CFM. With its range of 40 to 176 CFM, the HRV160 ECM covers continuous low-speed operation while retaining considerable reserve for peak periods—showers, cooking, and entertaining. An appliance that always runs at full capacity to meet its target is undersized: it is noisy, wears out, and costs more to operate.

In Quebec, compliance must also be verified against section 9.32 of the Building Code and CSA F326, whose total-capacity requirements are based on the number and type of rooms. We systematically check both methods and use the more demanding one.

Rebates, compliance, and realistic expectations

Let’s be precise, because much of the content online perpetuates confusion: in Quebec, an air exchanger installed on its own is generally not eligible for a direct rebate, unlike an eligible heat pump under the programs currently in effect. An HRV nevertheless becomes relevant as part of a Rénoclimat process, where improving the building envelope’s airtightness makes mechanical ventilation necessary, and it is required in Novoclimat-certified homes. Programs change regularly: we verify eligibility based on the specific case, one file at a time, before promising anything to a customer.

Maintenance, in three steps

• Every three months: rinse or replace the MERV 9 filter (SV18205). A clogged filter reduces airflow before anything else.
• Once a year: remove the core, wash it with warm soapy water, and check the condensate drain trap.
• Every fall: clear leaves, nests, and ice from the outdoor hoods.

A maintained unit preserves its performance. A neglected unit becomes a noisy fan that uses electricity without recovering anything.

The result, six weeks later

Follow-up check carried out in March: relative humidity stabilized between 43% and 49%, no more condensation on the living room windows, and the bathtub’s silicone seal was clean after washing. The customer summed it up more simply than we could have: “the house no longer smells musty in the morning.” The additional energy consumption associated with continuous ventilation remained marginal thanks to the ECM motors.

Our air exchanger installations in Montérégie and Greater Montreal

We install HRVs and ERVs in Sainte-Martine, Châteauguay, Mercier, Saint-Rémi, Beauharnois, and Salaberry-de-Valleyfield, as well as throughout Montreal, Laval, Longueuil, the North Shore, and the South Shore. Every project follows the same method: humidity assessment, documented airflow calculations, equipment selection based on the area’s actual climate, careful ductwork installation, and measured and recorded balancing before we leave the site.

If your home has fogged-up windows, persistent odors, or a bathroom that never dries, the problem is almost never the heating. It’s the ventilation. Contact AirGreen for an assessment of your HVAC system.