You will have a very serious moisture issue. Water will start condensing on things you don't want to get wet. To do what you want you will need a heat exchanger system that allows the warm outgoing air to heat the cool incoming air but will still send the moisture outside. I have not seen such a device but would be interested if anybody knows of one. Another choice is a ventless dryer. Popular in Europe where venting a dryer in old buildings is not possible, but they have there own issues.

I tried this years ago and if the machine is in the same room, not only is the moisture excessive from the dryer vent, but the intake air to the dryer is of course also moist, so you end up with much longer drying cycles. So any benefit gained from venting indoors for heat would be offset and as robert stated the damages resultant from the moisture could cost you substantial losses.

Has anyone heard of putting the vent tube in water to knock down the water vapor and dust that might come along?? I thinking 2 or inches or so underwater next to the dryer.

Big Al

Hello,
Using a dryer in a cold location adds to the drying time. Electric dryers will struggle to dry clothes. A gas dryer works marginally better. To stop lint from going everywhere, use a mesh screen. I used a pair of pantyhose for several years. USING A BUCKET OF WATER WILL CAUSE THE DRYER TO OVERHEAT. The air movement will be decreased when the friction from the bucket of water is added.

Isn't lint in the air explosive? Could be dangerous in an environment where a furnace or waterheater is, for example. This is why it's against code to vent a dryer indoors, isn't it?

There are some devices sold just for this purpose at some hardware stores...they look like little plastic boxes you attach the dryer vent hose to, add a tiny bit of water to catch some lint etc.. there's another one that's just a box fitted inline on the dryer vent with a damper in it for switching to "outside/inside" For occasional use I can't see it being all that harmful in the winter when the air in the house might already be bone dry.

While it can be said that indoor venting does recover a marginal amount of heat, it is quickly offset by the problems in introduces.

Try a simple experiment for yourself. Weigh a load of wet clothes when they come out of the washer, then weigh them again after they are dry. You can then estimate the amount of moisture by dividing the weight differntial by 8. (One gallon of water weighs 8.34lbs).

It must also be noted that the discharge from the dryer is approximately 80 to 100degF with 100% relative humidity. The basement is the coolest portion of the house which means that moisture will quickly condensate upon contact with the floor or walls, which then enhances the potential for mold to form on those walls.

In theory lint in the air could cause something like a dust explosion but you could never get the concentration high enough with just what comes out of a dryer so that is not a problem. Venting a gas dryer inside would be dangerous because of the fumes. Venting the electric inside will only cause problems with moisture, which can get expensive over time. If it was a good idea everbody would be doing it.

Big Al:

If the length of the duct run from the dryer - through the basement - and to outside is within rated capacity of your dryer, consider this:

1. You must not discharge moist air anywhere but outside (due to mold, swollen wood members, etc.)
2. The only heat you can expect is via radiation and convection from the duct itself as it carries the moist hot air through your basement and out.
3. If that amount of heat worth bothering, you need to install a sealed galvanized metal piping (ID=4, usually) with the negative gradient (a slop - look up how many inches per ln feet) to let all that water from the clothes to get outside by gravity.
4. You'll need a damper in the outside cap to prevent cold air from coming in.

It feels to me that it has to be a less contrived solution to your problem. But you are the only one who knows your habitat.

al

Venting indoors to recoup the heat is a good idea, in theory. In reality, it will eventually cause serious damage to your home. The moisture that your dryer is venting will get attracted to any cool object, eventually condensing. This will quickly cause mold and mildew to form, likely where you can't see it.

The only way to recoup the heat is either through a heat exchange in-line with the exhaust vent (which will not produce much heat) or to run a dehumidifier at the same time, killing any economic savings you would hope to achieve by venting indoors.

You don't mention whether you use a gas or electric dryer. If you use a gas dryer, do not vent indoors at all! CO poisoning is very real. The gas is odorless, colorless and tasteless. It sinks, so if your dryer is in the basement, your basement will be filled with it. This would make you have headaches, make you vomit and eventually (within minutes at the right concentration) it will kill you. Entire families in our city (Anchorage, AK) have been killed each year over the past two or three years due to CO poisoning, resulting in mandatory CO detectors in any home that burns a fossil fuel or has an attached garage. There were three close calls this season, alone.

My short suggestion: Don't vent a dryer indoors. A good alternative is to take up baking. Make a pot roast and pie every day and you'll be kept toasty. :-)

You know, if this were a great idea, everyone would do it.

I'm not even sure if this is to code. I can't imagine it is.

If you aren't heating your home adequately, get a new, more efficient furnace.

You could construct such a system with a two valve so that when it is hot the moist air is vented outside and when it is cold, the moist air is vented into your A/C / heating system. An easily accessible filter should be included in the line. You would want to have the A/C fan running when using the moist air to heat the house in order to distribute the moisture. You would also want to have the A/C turned off when this line was in use. I would also recommend investing in a hygrometer. Maybe you could design the valve to work with a humidistat.

Because our humidity here in Houston is pretty high even in the winter, I would want to recapture the heat through long copper ducts run inside the house that vent outdoors. Recapture a small percentage of the moisture might be nice at times.

I've been venting my dryer indoors during the winter for six years in two small houses and my folks have been doing the same for about seven years and neither of us have had any problems. Keep in mind that the locations in question have been Calgary, Alberta and Bozeman, Montana and both locations have extremely dry air in the winter. I live alone, so I do laundry infrequently; my parents do laundry considerably more often, but their house is large enough to handle the extra moisture. It's also worth noting that home humidifiers can pump more than a gallon of water per day into large houses in extreme winter climates and the "gallon of water per load" statistic applies to large loads of laundry that have been lightly spun; a fast-spinning front-load machine gets clothes fairly dry, right out of the washer. Since we're talking about saving resources, you *do* have a front-loader, right? ; )

The only time I've had an issue has been when the outside temperature is below -20C (roughly 0F), in which case windows near the dryer can experience considerable condensation. One solution is to vent the air outside for the most of the dryer's cycle, then let the air flow inside once the clothes are fairly dry.

To solve the lint issue, attach one leg of a finely woven pair of pantyhose to the inside vent with a tight-fitting elastic band. It looks absurd, but the large area permits air to flow with almost no restriction (much like the folds inside a car's air filter) and does a great job of removing lint. The air is nowhere near hot enough to cause me any concern over lint ignition, but it's still prudent to turn the filter inside out and vacuum it once in a while.

In summary, many of the above posts are alarmist nonsense and/or apply to warm, moist climates that would benefit little from this energy saving trick. For those of us with cold, dry winters, a couple small tricks make this a great way to save energy and provide beneficial humidity.

(In case someone reading this has somehow missed the disclaimer: This DOES NOT apply to gas dryers!)

My house on a river has a poured cement above ground basement. We don't use it as anything much because of flooding but we do have the dryer and washer down there. This area is not heated. Our water pipes( to the washer) froze up and we were wondering if we could vent our electric dryer inside this area. We do have a sheetrock ceiling with installation. Would this cause too much moisture? The rest of the basement is just the poured cement walls and some flood vents. The basement is so cold.

You can recoup the heat and humidity from the dryer. The added subtle benefit is that if your dryer is not venting outside, your house is not pulling in new air through infiltration at ambient outdoor temperatures to make up for the vented air. You are potentially saving the difference between ambient to 90F for all of the air you keep in the house. I have a diverter on mine so I vent outside in the summer. The diverter has a little mesh screen, and then I take that outlet to the container with the water in it. You can buy all the parts at hardware stores or online. I like having the ease of the diverter and the water bucket to catch lint, even though I don't see a lot of lint in the water. In the winter my humidifier run significantly less (I have it on the first floor and not the basement, and it was around a gallon a day before, now a gallon every 3-4 days). My washer does a good job at drying, and usually I run an extra spin cycle when it finishes, but I don't have any issues with excess humidity.