Heat‑pump dryer
A standard dryer uses electrical resistance to heat the air that dries your clothes. It then evacuates the hot, humid air outside your home. Models equipped with a heat pump are more energy‑efficient and use a heat‑pump cycle to heat the air. These ventless dryers, which do not evacuate heat through a dryer vent, are often called heat‑pump dryers.
You could receive financial assistance for the purchase and installation of a heat‑pump dryer with the LogisVert Efficient Homes Program.
How it works
Unlike conventional dryers, the hot humid air is not expelled outside the home. It goes through a heat exchanger that condenses the humidity and generates condensation—the condensate. The hot air‑now dry‑returns to the dryer drum to continue drying the clothes. The condensate is evacuated through the same drain as the one used for the washing machine.
Stages of the operating cycle of a heat pump dryer
- The hot air coming out of the drum is loaded with moisture from the clothes.
- The heat pump absorbs heat from the air coming out of the drum, thus condensing the moisture which is extracted in the form of water.
- The dry air returning to the drum absorbs the heat recovered by the heat pump.
- In the drum, the hot dry air picks up moisture on contact with the clothes and the cycle begins again.
- A pump sends the water extracted from the clothes into a recipient which must be emptied. Optionally the water can be sent into the washer's drain pipe.
A great compromise
heat‑pump dryers are estimated to need about 25% more drying time. The refrigerant used in the dryer is a source of greenhouse gas emissions and some contain HFCs.
However, the following is also true:
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They lead to electricity savings of 30% to 60% compared with traditional models.
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Air doesn’t need to be vented outside, which limits air leaks in the house and therefore reduces heating needs.
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Less maintenance is required given that there are no vents to clean.
Look for ENERGY STAR® certified heat‑pump dryers—they are the most energy‑efficient.
