Clothes dryer to heat pump energy recovery

jray3 · 10-30-14, 06:52 PM

Greetings from an EcoModder, new to EcoRenovator.

I'm trying to make some lemonade of the fact that my clothes dryer vent exhausts right onto my outdoor heat pump compressor and coil. Luckily, this is a heating-dominated climate. Idea is to create a 'winter mode' such that the dryer only runs when the compressor is running, and to do so simply by supplying the voltage to pull in the dryer's main contactor from the HVAC compressor relay. This would cause the dryer to turn on and off in sync with the heat pump. I'd also include a switch to return to stock configuration as a summer mode/manual override for faster drying when necessary. A seasonal hood that directs more dryer exhaust into the compressor coils would also be used (made of heavy vinyl or corroplast).
If I'm good, that same hood could be repositioned to keep exhaust away from the coils during summer.

Upside is energy savings, potentially better net effect than the new closed-loop heat pump clothes dryers that sell for $1500-1800..
Downsides could include coil icing due to all that humidity, as well as lint buildup on the coil (which I already have to clean off regularly).

Anybody tried something similar? I've already reviewed the thread discussing homebuilt heat exchangers, and plan to add venting and weatherstripping to the laundry room doors to pull dryer process air from the cool dry garage rather than the warm and humid house.

10-30-14, 06:52 PM	#1
jray3 Lurking Renovator Join Date: Oct 2014 Location: Tacoma, WA area Posts: 2 Thanks: 0 Thanked 0 Times in 0 Posts	Clothes dryer to heat pump energy recovery Greetings from an EcoModder, new to EcoRenovator. I'm trying to make some lemonade of the fact that my clothes dryer vent exhausts right onto my outdoor heat pump compressor and coil. Luckily, this is a heating-dominated climate. Idea is to create a 'winter mode' such that the dryer only runs when the compressor is running, and to do so simply by supplying the voltage to pull in the dryer's main contactor from the HVAC compressor relay. This would cause the dryer to turn on and off in sync with the heat pump. I'd also include a switch to return to stock configuration as a summer mode/manual override for faster drying when necessary. A seasonal hood that directs more dryer exhaust into the compressor coils would also be used (made of heavy vinyl or corroplast). If I'm good, that same hood could be repositioned to keep exhaust away from the coils during summer. Upside is energy savings, potentially better net effect than the new closed-loop heat pump clothes dryers that sell for $1500-1800.. Downsides could include coil icing due to all that humidity, as well as lint buildup on the coil (which I already have to clean off regularly). Anybody tried something similar? I've already reviewed the thread discussing homebuilt heat exchangers, and plan to add venting and weatherstripping to the laundry room doors to pull dryer process air from the cool dry garage rather than the warm and humid house.