Unlike traditional tumble dryers, a washer dryer does not vent in the typical sense by expelling hot, moist air outside or into a room. Instead, washer dryers utilize a different method for drying clothes.
Understanding Condenser Drying
Washer dryers function as condenser dryers during the drying cycle. This means they use a condensation process to remove moisture from clothes.
The Condensation Process
Here's how the drying process works in a washer dryer:
- Hot air circulates through the drum, picking up moisture from the clothes.
- This warm, moist air then passes through a heat exchanger or condenser.
- Cooler air is drawn in (often from the room or via a cooling circuit), which cools the warm, moist air from the drum.
- As the moist air cools, the water vapour within it condenses back into liquid water.
- This condensed water is then automatically drained away by the machine, typically using the same pump and drain hose used for washing.
Because the moisture is collected and drained as water rather than expelled as vapour, washer dryers do not need a vent hose or an external wall opening.
Why No External Vent?
The key benefit of the condenser drying method used by washer dryers is their installation flexibility. Since they condense the moisture and drain it away internally, there is no requirement for an external vent to the outside of your home. This makes them suitable for apartments, homes without easy access to an external wall, or any location where installing a vent would be difficult or impossible.
In summary, a washer dryer doesn't vent hot, moist air; it condenses the moisture and drains it away.
