Condensing dryer advice
coz24
| Posted in Green Building Techniques on
Does anyone have any experience with these? can you get the HRV to distribute the heat that is created? do they work fairly well or does drying time increase substantially? Do they make too much vapor for a high performing home in zone 6 in the winter time? Thank you in advance. And thank you GBA you make a world of difference for me, a developer of Net-zero homes!
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Replies
Susan,
For more on condensing clothes dryers, see this article: Alternatives to Clothes Dryers.
For more on heat-pump clothes dryers, see:
Heat-Pump Clothes Dryers
Energy-Saving Clothes Dryers Hit U.S. Markets
Susan- We have had a Whirlpool heat pump dryer since June. It works very well. On "Eco" setting, the most energy efficient, it seems to take a little longer than a typical dryer, but not excessively so.
There is no vent, so no hole in the building envelope. The dryer condenses the moisture and it runs into the same pipe the washer empties into, so no water vapor as far as I can notice.
An HRV isn't really designed to move heat around the house. The flow is too limited. Our house is on a single level. Our dryer is in a mechanical/utility room, so we leave the door open and whatever heat is produced does spread around a bit.
I understand you can also buy a condensing dryer that doesn't use a heat pump. I have no experience with them, but have heard they are very slow.
The main drawback to our dryer is cost. We paid about $1400. You save a bit on installation, since you don't need to punch a hole in the wall and run a vent. We have been very happy with it.
Yes, we have a combination LG washer/dryer that is a condensing dryer. We use the dryer infrequently because we hang clothes outside and/or inside as much as possible. House is in zone 6.
If you have a high use dedicated laundry room, you might want to factor that into an HRV setup...but some type of specific HRV/dryer connection doesn't make sense.
I believe drying times are longer, but I haven't paid much attention to actual times and haven't found it to be an issue.
Vapor shouldn't be an issue if the house has a well functioning ventilation system and doesn't have pre-existing high humidity issues.
Normal vented dryers collect hair, dog fur, and clothing fibers in the filter. That is one thing I've noticed about our condensing dryer...because the clothing isn't blasted with vented hot air, the dog fur tends to stay put on the clothes and some has to be cleaned off the drum.
The obvious benefit is that there is no clunky duct and wall termination to setup, our unit is also 120v and plugs into a regular outlet. We are happy with the purchase and no hole in the wall outweighs any differences from a regular dryer, for us.
Dog fur?
Our heat pump dryer collects the dog fur in the lint filter just like our previous vented dryer did. No fur on the clothes and none on the drum.
Unlike Brian's, our dryer requires a typical 30 amp, 240 volt power supply.
We've had the Whirlpool heat pump dryer since May and it works nicely. At the most energy efficient setting ("Casual" with "Eco" mode), it takes 86 minutes for a standard load of kids/adults clothes. You do need to vacuum the secondary lint filter every 3-5 loads (the machine prompts you every 5, but it can need it in 3 or less depending on how much lint a load generates), so have a vacuum nearby. We have a central vac outlet right there, so it isn't a big thing.
We are in Zone 5 and have an ERV, but the laundry room isn't connected to the ERV. We leave the door open and the heat spreads itself around. Not noticeably warmer or humid in the laundry room. I will say that in the summer, using the dryer makes the laundry room a good bit warmer if the door is closed.
Stephen, in post #2 you mention using the "Eco" setting. Do you also use the "Casual" mode selected using the round selector? That will give you the best energy efficiency. Whirlpool mentions it on a sticker you can see when you open the dryer door, right above the drum opening.
This is incredibly helpful.The distinction on the dog hair is so useful and not something one can find out reading technical information, really appreciate it. I can now offer both to my buyers with the relative merits disclosed clearly. I am using an air handler with semi-ducted Mitsubishi ASHPs on these houses that will be linked somehow, ( I have someone that knows more than me working on this) to the HRVs so they work in concert. Thank you Martin, Stephen and Brian.
It's been at least a few months since I used the dryer function, so I don't remember well what machine dried clothes are like. This post also reminded me to check the pump filter and I found a clump of wet dog fur. This LG combo machine doesn't have a lint filter. I just read the manual again.
What I do know is we have a black dog that sheds a lot and we should brush him more. If only using the wash mode, we do find some fur in the machine at the end, often near the door and gasket area. My distant memory of using the dryer mode is that there is still some dried fur leftover.
I'm still thumbs up on the condensing dryer, but sounds like Stephen's heat pump dryer (or other types with a lint filter) might be a better fit if dog fur is a concern.
After brushing (in the old rental house):
Brian- that dog looks pretty miffed at the loss of his fur:-)
CB-thanks for the tip about the casual setting.
I want to make sure it's clear that there is a big differences in energy consumption between a condensing dryer and a heat pump dryer. A condensing dryer uses a little more electricity to dry a load of clothes than a regular vented dryer does. A heat-pump dryer uses much less. In fact, a heat pump dryer is almost as efficient as using a clothesline indoors in the winter. (A clothesline indoors in the winter might seem to use no energy, but it provides evaporative cooling to the space it's in, and thus requires your heating system to work harder.)
You will want to mov fast if you want to pick up the Whirlpool Hybrid Heat pump dryer. They've discontinued the product (at least for now) but you may be able to find some sale models still available. We've had ours for a year and love it. I waited several months without a dryer when these came out just so I could avoid buying a condenser.