Air supply for gas dryer in a closet
DML
| Posted in Energy, Heating & Insulation on
I am building a staked washer/dryer into a closet in someone’s kitchen right now and want to avoid cutting louvres into the door, for the air flow needed. Not only are they not very attractive, but I will also be drawing conditioned air from the kitchen and blasting it outside, which doesn’t seem so sensible.
I would think it is therefore possible to provide the closet with it’s own exterior air source, but would like to know what the steps are in doing this, i.e. is there a sizing requirement, do I need some sort of check valve/flap.
Thanks
Replies
Check with the installation manual
We allow 36 square inches per dryer( that's 18" high and 18"low)
That is for gas or electric dryers.
Do you mean this would be the size of the louvres? The louvre sizes I know, but I am trying to avoid the louvres. One argunment would be that it is a 4" duct being used to evacuate the air, do you just need a 4" duct to let air back in, but this is not congruent with an 18" louvre. Hence my question!
Thanks
I'm pretty sure Butch means 36 square inches, not 36 inches squared. A hole 6" x 6" is 36 square inches. He puts two for a total of 36 square inches. I'd think two 4" dia vent caps would do. The flappers might be the tricky part. I'd be interested to see how this is done in cold climates...and places with wasps and sparrows.
Al Mollitor, Sharon MA
Yeah, 36 square inches, and some mostly solid louvers need to be a lot larger to provide that much effective surface area.
There's a certainly logic to "4-inch duct out suggests 4-inch duct in."
HOWEVER, it doesn't work that way. The dryer needs to be quite free-breathing on the inlet side. All of the fan's ability to push/pull air is dedicated to pushing out the exhaust duct work. The allowable length/diameter/type of ductwork factors assumes that. If you restrict the inlet much at all, the dryer's fan may not have enough oomph to move enough air.
Ballpark - an 8" round duct would provide a goodly amount of make-up air at very low pressure drop. A 6" duct would probably be okay. If you ran it from the rim-joist through the crawlspace to the floor of that closet, you could have a tight sealing door. You'd want a tight-sealing door, maybe even an exterior one, if you go make essentially a big leak to the outside.
Another way to view the loss of conditioned air is that the dryer doesn't have to heat the air as much (i.e. clothes will dry a bit quicker) and, if your house is somewhat tight, the more air you move, the better the indoor air quality.David Thomas Overlooking Cook Inlet in Kenai, Alaska
I'm pretty sure Butch means 36 square inches, not 36 inches squared. A hole 6" x 6" is 36 square inches. He puts two for a total of 36 square inches. I'd think two 4" dia vent caps would do
Yes I did mean 36 square inches but you would need two 5" vents, one within
12"of the floor and one 12" of the ceiling
This does not include any blocking effect your "louvers" have on the size of the opening
I'm not to clear on what you meant by that (louvers) and if you mean bringing air
into the closet from outside or from, through the closet door.
But once again what does the installation recomendations have, they supercede
anything anybody here might have to say about this
a 1" gap under this closet door will provide all the make-up air this dryer needs.