Maintaining your Heat Recovery Ventilator

Your heat recovery ventilator (HRV) can help make your house a clean, healthy living environment. It improves air quality by removing stale indoor air and continuously replacing it with preheated outdoor air.

An HRV can give many years of trouble free service. All it takes is a little bit of time to keep it running smoothly. The following maintenance schedule is easy to do and takes only a few minutes.

Before performing any maintenance always turn off the HRV and unplug it.


1. Clean or Replace Air Filters: Dirty or clogged filters reduce air flow and ventilation efficiency and should be cleaned about every two months. Open up the front panel and remove the filters. Clean with a vacuum cleaner then wash with mild soap and water before replacing. Older units may have replaceable filters.

2. Check Outdoor Intake and Exhaust Hoods: Check that the outside vents of your HRV are not blocked. Remove leaves, waste paper etc. During winter, clear any snow or frost buildup blocking outside vents.

3. Inspect the Condensate drain: The condensate drain is usually a pipe or plastic tube coming out of the bottom of the HRV. Slowly pour about two liters of warm, clean water in the drain inside the HRV and watch to see that it is flowing freely. If there is a backup, clean the drain.

4. Clean the Heat Exchange Core : Check your HRV owner’s manual for removing and cleaning the heat exchange core. Vacuum and clean with mild soap and water.

5. Clean Grilles and inspect the ductwork: Once a year, remove and inspect the grilles covering the ends of the ducts leading to and from the HRV. Vacuum if necessary.

6. Service the Fans: Make sure the unit is unplugged. Gently brush and remove dirt that has accumulated on the fan blades. Check your manual to see if lubrication is recommended. Older models may require a few drops of lubricating oil whereas newer models are designed to run continuously without lubrication.

7. Arrange for Annual Servicing: Your HRV should be serviced annually by a qualified technician accredited by the Heating, Refrigeration and Air Conditioning Institute of Canada (HRAI)


Turn your HRV off in April or May by either turning the dehumidistat control to HIGH setting or OFF
Turn your HRV back on in September or October and reset dehumidistat to 40% to 80%