Help your home breathe better

Maintain exhaust fans, as well as ventilation, heating and clothes dryer ducts

Every year, once the cold weather has set in for good, the doors in your house are open only to let people in and out, and chances are your windows will stay completely shut for the entire winter. During these long months, your home and its occupants are basically on artificial respiration. The air you breathe is introduced into the house, circulated and then evacuated outside by a network of ducts connected to a system that can include an air exchanger, heat recovery ventilator (HRV), forced-air heating system, bathroom ventilators, range hood, clothes dryer duct, etc. The question is: Are all these ducts—and the air moving through them—clean?

Heating ducts
In forced-air heating systems, the greatest dust and debris accumulation is in the return air ducts (commonly called “returns”). To clean them, simply remove the register grilles and vacuum out the ducts, with a brush attachment installed. Unless you have young children and/or longhaired pets, performing this dusting operation once a year as part of your spring cleaning should be enough.

If there is water accumulation in your ducts, you are moving into a newly constructed or renovated house, or the airflow from the furnace or other heat source seems abnormal, more extensive cleaning of the returns will be necessary, and for this job you will need to call in a professional. One caveat, however: never agree to have a contractor spray a pest control product into the ducts. No such product is registered in Canada for this purpose. Canada Mortgage and Housing Corporation further advises that effective duct cleaning “does not require the use of a biocide.”

Ventilation ducts
Air exchanger and HRV ducts, however, be they of the rigid or flexible type, can only be cleaned using specialized equipment: because of the way they snake through wall and floor cavities as well as their fragility (in the case of flexible ducting), you cannot use a household vacuum cleaner for the job. Sometimes, the pleated sheathing of a flexible duct will have been stretched too tight, making cleaning out of the question. In the latter case, unfortunately, replacement is the only solution.

So how often will these ducts require cleaning? It depends on your household. In a house with no range hood that is home to two adults who smoke, two children and a longhaired cat and dog, the ducts will obviously get dirtier faster. A good clue as to whether you should be thinking about contacting a specialized cleaning firm is how clean the inside of the device and the register grilles are—it’s usually a good indicator of how clean the ducts are.

Exhaust fans and clothes dryer ducts
Bathroom ventilator and kitchen range hood ducts normally don’t require systematic cleaning. A simple check of the outside exhaust flaps connected to these ducts will help you diagnose their condition: if the flap doesn’t open, or opens only a little with the fan on, the vent may be blocked or ducting may have come unhooked somewhere.

Your clothes dryer duct, on the other hand, requires regular attention. Disconnect it from the dryer and remove, by hand or with a vacuum cleaner, any lint built up in the duct. This will maintain the efficiency of your dryer and reduce the risk of fire.

Outside outlets
It’s also essential that you check all exterior outlets, flaps and hoods: if these are blocked, your air exchanger or HRV will be “short of breath,” while flaps that are stuck open will drive your heating bill up. Your seasonal maintenance rounds provide the ideal occasion to take care of this. Remove anything that may be blocking the outlets. Besides leaves, paper debris and lint, you might even find a bird that has moved in, seeking a little warmth and comfort!

No matter how clean and unobstructed they are, the ducts in your home—its respiratory passages, if you will—won’t contribute to optimum performance by their corresponding heating and ventilation apparatus unless their filters and fans are properly maintained. Refer to the manual instruction for each device for the ideal cleaning and parts replacement schedules.

The filters in the latest-model air exchangers and HRVs are usually easily removable, as are those in range hoods and clothes dryers. You can then simply vacuum the dust off, or wash with water and a mild soap. Regular maintenance of the filters in a forced-air heating system will guarantee smooth operation and ensure that the air circulated has been stripped of particles that are dangerous to your health.

And while you’ve got the filter removed for cleaning, you may as well take the time to dust off the blades on the fan that it normally covers.


-  Canada Mortgage and Housing Corporation
-  Suppliers recommended by CAA-Quebec Habitation