recapturing dryer heat?

Has anyone tried to use a heat exchanger of any kind on their dryer vent, or better yet, is there any commercially available product to do this? I have a gas dryer so simply venting indoors likely isn't a good option, as welcome as the extra humidity may be the few months out of the year that I'd actually want to do this.

I realize that it's probably inconsequential in the grand scheme of things, but it does seem wasteful to heat all that air and then just blow it outdoors when it's 20 degrees out.

I tried to do a quick online search, but all I saw was a little discussion and not much in the way of actual plans, products, or results.

nate

Reply to
Nate Nagel
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my dryer had some rotten cardboard lining the inside of the door that served to insulate, i ripped that off, now the front door gets nice and hot so some heat is recovered there..

also use an extra long METAL vent hose and a lot of the heat will be recovered that way too....

if you put any significant money into this, it is unlikely that you will get a return on the investment..

Mark

Reply to
Mark

You don't want to recover TOO much of the heat unless you use a "condensing" heat exchanger, otherwize the moisture you took out of the clothes is going to run back into the dryer or make a big icycle at the vent.

Reply to
clare

It's one of those things that has been contemplated for eons. The reason that there is not a product for the purpose is that there are too many issues to overcome, like humidity, condensate, corrosion, back pressure, lint buildup, etc. and too little to gain, something like 15,000 BTU for

30 min.
Reply to
Pete C.

Could make a J tube of sorts, to catch any condensate.

I think the suggestion about using more ducting was good. It's perty cheap, and you can just run it around all the floor or ceiling corners, or some kind of serpentine config.

Unless you can control the humidity, that warm air is just too damp to vent inside.. They make indoor lint traps (water baths), and even with those, we eventually just vented it right outside.

Ditto "ventless" gas heaters -- they'll soak a wall.

Proly the best thing for saving money on a dryer: A front loader with a high-rpm spin cycle. You can almost hang the clothes right out of the washer. Rarely do you find a win-win-win-win-win-win situation as with front loaders.

Reply to
Existential Angst

Once in a while, I will vent the dryer into the house. I try to keep the lint dust down by covering the far end of the dryer hose with a knee high nylon hose. hth.... Linda H.

Reply to
Linda Hungerford

Well, the avg electric dryer is over 4,000 watts -- 4 kWhrs per hour of running time, which, at net NY rates, is about $1. If you could recoup 1/4 of that, you're earning 25c an hour.

Reply to
Existential Angst

It takes very little additional ducting to destroy a dryers performance. Add 10' and perhaps a bend or two and you'll be looking at two hour dry times.

Reply to
AZ Nomad

Google for "dryer+vent+valve"

Here's one:

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When you start the dryer, you flip a lever and the dryer exhaust enters the room instead of being wasted outside. This has two advantages: You get the heat, you get the humidity.

On the down side, you'll have to put up with all the folks who will say "You're gonna die a horrible death, covered with fungating pustules and dripping sores!", particulrly if you have a gas dryer.

As for being inconsequential, not so. Thirty minutes of drying time will turn your utility room and anything nearby into a plenty-toasty territority, plus you'll be helping to save the planet.

Reply to
HeyBub

Duct booster? Heh, starting to get complicated already....

Reply to
Existential Angst

Been doing this for 30 years with an electric dryer. The heat and humidity are welcome. The lint is another story. In the basement it was not a problem. However, in a home with the dryer in the living quarters, you might want to do as this person says, filter the air to remove lint. But, you have to clean it after every use, just like the filter in the dryer itself.

Reply to
Art Todesco

I have seen a commercial dryer heat exchanger in the past. I don't know if they still make them.

This is interesting:

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Reply to
Van Chocstraw

exchanger of any kind on their dryer

Gas vs Electric dryers are two different stories. Electrics can vent indoors with only the lint problem, we have been doing this for the 51 years we have been married. But gas presents a problem with the fumes and humidity combined. If it were my situation, I would just place a fan near the exhaust piping and blow air over the piping and recover a little bit of heat that way, but at a negligible cost.

Reply to
hrhofmann

at exchanger of any kind on their dryer

Our electric dryer vents into the greenhouse during the winter, saving some of the heating costs.

Paul

Reply to
Pavel314

I'm running about 8' and a couple of 90-degree elbows and it's not bad

- about an hour for a full load (electric dryer). No condensate issues, either (I sited it in the basement right next to where the sump pump will be going, just in case).

One thing that is worth doing is dismantling the dryer every couple of years; they really plug up after a while, even if the airflow coming out still seems good. Sometime I'll get a wild hair and make a proper access panel for the back of ours (the whole back has to be removed right now, plus it extends underneath the machine so the whole lot has to be turned over to get inside)

I've thought about recovering heat from ours in the past, too (as recently as a week ago, actually) - but I'm just not sure that it's worth it, at least not for anything that uses power to do the recovery. We run the dryer for around an hour a day, and given the 23 hours it's not running, I'm probably better off insulating the heck out of the pipe to reduce heat loss from the house, and save more money that way.

cheers

Jules

Reply to
Jules

The previous poster was suggesting more than 8' and a couple of 90 degree turns. He'd be lucky if he managed to dry a load of clothing in under

5 hours and if the dryer didn't shut down due to overheating.
Reply to
AZ Nomad

Reply to
JIMMIE

One of my DIYer friends down in Ga. mounted a gutted out service panel on the wall above his dryer. Normally the air flows from the bottom back of the box through an HVAC filter to the front of the box and out the top to the vent.To dump the warm humid air into the house he just opens the door on it. I don't know if or how he provided for keeping the cold air from coming down the vent.

Jimmie

Reply to
JIMMIE

I usually do it when the humidity is really low. Sometimes, like the last couple of weeks, the humidifier just cant keep up.

Jimmie

Reply to
JIMMIE

I have "restored" a couple of "non-working" dryers by taking outside, and blasting out all the air passages with a large blaster nozzle on my air compressor hose. You'll be amazed at the crud that comes out. After that, they worked fine.

O.P. If you add duct to extract more heat, use a larger size duct so you don't restrict the dryers air flow.. This will also give it more heat exchange area. Just make sure you clean out the inside regularly, or it will become insulated with lint, and become a fire hazard.

Reply to
Bob F

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