It looks like the Whirlpool one is vent less and should be out soon.

Yes, but why is the LG one vented? Why would ANY heat pump dryer need to be vented?

A review of the Whirlpool ventless dryer is here:


http://laundry.reviewed.com/content/whirlpool-duet-wed99hedw-heat-pump-dryer-review


Roger

I would guess that tossing clothes around for 1.5 hours causes of lot of abrasive wear. Would be interesting to see data on this issue.

Do you think these need surrounding air space like a heat pump water heater? I am planning to install a dryer in a fairly confined space (closet) . Wil lbe doing this next summer so there is some time to feel it out.

I once saw a really cool passive house with an exhaust vent through an hrv that hung in the laundry room. The laundry room had drying racks and right above them was the exhaust that evacuated the moist air. I think it's ideal. A clothes dryer is not only unnecessary, it shortens the life of your clothes.

Evaporation takes a lot of energy and a HRV dumps this latent energy outside. So you need significant heat to prevent the room temp from dropping. I expect that putting a dehumidifier in the laundry room is more efficient - no latent or sensible energy is transferred to the exterior.

There is no mention of cooling air but I would assume that since it's a heat pump, it's operates just like a heat pump HWH and will put out cold air?

A comparison of the models discussed above is here:

http://laundry.reviewed.com/content/lg-dlhx4072w-heat-pump-dryer-review

It clarifies why the LG is vented: it is a dual-mode dryer: can use the heat pump function or work as a regular, vented dryer.

Beginning to see a decent number of reviews of the whirlpool vent-less unit:

http://www.whirlpool.com/-[WED99HEDW]-1022543/WED99HEDW/#ratingsandreviews

This is more effective if you share picture of that LG dryer. you need to share some more detail of that dryer. The LG is a very good brand, so i have a believe that LG is good brand so they provide good product.

[quote]
Posted By rlsmith017 on 04 Apr 2015 11:40 AM
Beginning to see a decent number of reviews of the whirlpool vent-less unit:




http://www.whirlpool.com/-[WED99HEDW]-1022543/WED99HEDW/#ratingsandreviews
[/quote]

From the linked reviews:
" I like my clothes to come out of the dryer smelling fresh and clean! That's why I buy scented detergent! Since this dryer constantly recycles the air, the scent of the detergent/fabric softener does not fade nearly as much as with my old vented dryer. Clothes smell nice and fresh coming out and retain their scent for much longer."

One person's nice & fresh is another person's disgustingly perfumed.

The whirpool is out and the reviews are really good. Home depot has them on sale! If you happen to live in Idaho, Oregon, or Montana, there is even a $450 Factory rebate!
I just paid $1298 for a net cost of $848. That is a no brainer!!!

Does the heat pump dryer emit cold air when it's running?

It uses energy so 99.99% likely gives off heat....heat pumps just move heat so it acts like a dehumidifier and cools the air to get the moisture out of it and then heats the air backup so it can be sent to the cloths to take more moisture from them. Just keeps doing that cycle.

It uses a 30A circuit - expect it to generate a lot of heat that has nowhere to go (unlike a HP hot water heater where it goes into the tank and then down the drain). Helpful in winter, inefficient in summer.

The heat is recycled back into the unit. Because the unit needs heat to dry the clothes, the heat is recycled back so the heating load is reduced. The moisture is extracted, and goes down a drain. It is unlike a HPWH as the heat does not go elsewhere leaving a cool air emmission. And of course the added benefit of being ventless is bigger than many recognize. A typical dryer exhausts about 120 CFM, that air will be replaced by outside air. A typical 1500 sq ft home will get approximately 1/2 of it total air volume replaced during a 45 minute dryer cycle. If its -10 outside that is a pretty significant load.

Thanks, sounds pretty good.   


I see the price online $1298.  VT residents also get a $400 rebate.

Unless it is 100% efficient, it consumes power so it WILL generate waste heat, it has to... If done right however, the waste heat is incorporated in the process to raise overall efficiency. There will still be a residual net gain in heat when the cycle is complete. Interesting concept though, use heat pump to concentrate heat so the cloths more easilly give up their moisture. Then run that warm moist air back thru the evaporator to reclaim/recycle the heat and in the process dehumidify the drying air.(sounds like someone got bored and ran their dryer on air dry only and cycled that air thru their home de-humidifier) The dehumidified air is of course way more efficient at absorbing moisture than regular room air, kind of like the car defroster is way better at clearing moist car windows when the air conditioner is turned on. It sounds counter intuitive at first, "I want the car warm, I don't want the A/C on". I learned how effective this is when I bought a Mitsubishi Eclipse. The A/C control is hard wired to the defroster and it works great. I had the A/C clutch bearing fail so had to disconnect this function for a while. Without A/C it takes a LOT more time to defog the windows in a cold car.

This dryer sounds especially usefull in cold winter climates where, as mentioned the large air exchange is a huge home heat load. Residual heat gain would not be my ideal in a hot climate though...

Assuming it leaves the house moisture level the same (it could be designed to raise or lower it), ALL of the electricity it consumes ends up as heat that is released into the interior. Ultimately, there is no "recycling". OK, a little bit of heat may go down the drain with the water. This is basic closed-system physics.