Electric clothes dryer unventing
Regrettably in the US there are NO vent less heat pump clothes dryers. Obviously simply not venting would cause unacceptable heat gain and really bad humidity gain. However, With a small hack on essentially any conventional electric dryer it’s inlet air supply can be collected to a single duct, it’s outlet is already in a duct. Now these two ducts can be routed to a “passive” HRV, mounted above the dryer in the laundry room, ( a passive HRV has no fans) and the other two ports of the HRV simply left open to the room. The drain lines from the HRV would be routed to the laundry sink. The hot wet output of the dryer will be cooled and dehumidified by preheating the air flowing into the dryer. Because both processes are imperfect I’d still expect the indoor air would rise in temperature and humidity but none of the energy would be vented. Some of the energy used would be recovered by preheating the air going into the dryer so fewer watts should be used but the efficiency would still be well below what a heat pump could do. Drying times may be lengthened slightly. Lint will require more maintenance than a typical HRV. I see no way of predicting how bad it’ll be. NU-AIR makes what looks like a suitable passive HRV model NU120-2 The NU-AIR has a filter for one air stream, I’ll connect that port to the dryer output and see how effective it is, I’d start by checking and cleaning the filter after each load. Hopefully the core will be largely self cleaning as the condensed water caries what is missed by the filter. I’m ready to try it! If i didn’t live in such a backward country I would rather just buy a heat pump dryer as any European can. Has anyone tried it? See any serious problems?