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by ct0 1164 days ago
In your experience, does your heat pump dryer actually dry in a similar amount of time to a conventional electric dryer?
3 comments

Nope, the toaster had a full load done in like an hour. The heat pump is like 3 hours. But the difference is the heat pump doesn't absolutely destroy my clothes. I'm noticing how much longer my clothes are lasting since switching. It's also so much quieter than the electric.

If you are the type of person who goes "oh crap I need to wash every piece of clothing RIGHT NOW" then heat pump isn't for you because of the time penalty.

Specifically, what the heat pump dryer is doing is basically pulling air through the clothing which evaporates some water from the clothes into the air, then cooling the air, which causes water to condense, removing the condensed water and warming the air back up to send through the clothes again. The effect is much closer to the clothes hanging from a line in a garden on a perfect drying day, except it's inside a box.

Whereas the other way to do this is just cook the clothes and the water evaporates, then you dump the warm moist air either outside or into a separate dehumidifier which throws much of the energy away. As you observed this is faster, but most people don't need faster if it's unattended. My dishwasher is slower than washing dishes by hand, but I don't need to sit there watching while it does it so who cares?

My heat pump drier dries a full load (8 kg) of cotton in about 4 hours. My only other experience was a huge, old unit when I lived in North America and I don't really remember if it was faster, but it absolutely destroyed any piece of cloth that wasn't resistant enough, especially anything with elastics.

My current one is as gentle as air drying, no destruction at all.

I have installed condensate dryers which are actually more efficient than heat pump dryers but take a couple of hours to dry. They don't need to be vented to the outside.
My heat pump dryer doesn't vent and captures the water to a tank or pumps it down the drain.