Mikey said:
A neighbor just bought a Bosche "condensation dryer" to avoid having to vent a conventional dryer. Apparently it uses running water somehow to condense the moisture removed from the clothes, and the waste water drains out the washer drain standpipe. All in all, it sounds like a lousy idea to me, especially if you're on a well with hard water and a septic system, but I'm open to the thoughts of others.
I couldn't find much on the Bosch dryer but there were reviews on the Hotpoint. Both seemed to be sold mostly in the UK. There are a lot of places in the UK where the municipality supplies water without a meter.
Comparing the Bosch standard and "condensation" dryers, the latter used about 7% more power (kWH) for the same size dryer. The difference was 4.2 vs. 3.92 kWH for a 7 kg load.
Users indicated that the indoor discharge created sauna-like conditions from the added heat and humidity. The condenser doesn't take out all of the humidity. They also took longer to dry a load of clothes.
The added heat and humidity would be ok in the winter heating season, but would increase the A/C load during the cooling season. I estimate about 2 kWH of added A/C power to remove about 20,000 BTUs worth of heat and humidity from one dryer load. Water cost is extra if you have to pay that bill.
They don't have a lot of A/C in the UK so it is probably not a factor over there.
Purchasers of the Hotpoint (only consumer reviews available) reported abominable reliability.
