Is it possible to attach a diverter to an electric clothes dryer vent so it can help heat my house in the winter? Seems like such a waste to blow it all outside. I imagine you'd need some sort of filter or maybe a radiant heating option.
Yes. You can get an indoor lint collector that allows you to vent the dryer exhaust indoors. They're simple and cheap but also direct all of your dryer exhaust into your house, including all the moisture.
A more expensive option is a full heat exchanger which attempts to just transfer the heat and nothing else. You have to filter the lint first, however, or you're going to clog the exchanger.
There are dangers associated with recovering heat this way (NDSU 2008). Be sure you're familiar with them.
Here in Wisconsin we do it just as Billy alluded to: a filtered bypass vent. You can use the damper to bleed off a little or a lot of the hot air/moist air into the home. The units are around $20. Be advised that you should place a fan or other means of circulating the moist air, as it will make your dryer room VERY moist if not pushed out into other areas. As with all things there is no pat answer. Use diligence and it will help. It is not a open and run 100% of the time option though if you do multiple loads for a medium/large family...
It seems that many of the people here are simply answering based on their personal experience for their particular scenario. Fact is, in the winter most homes NEED more humidity hence the reason people by humidifiers that they run in the winter time. So to say that it’s not a good idea because of the moisture is NOT applicable in all situations. During the winter (which is when you would be using your dryers heat to heat the home) is when the extra moisture would be welcomed in most cases. So you can’t simply say it’s not a good idea because of moisture. It’s just not true. You have to look at each scenario based on its on merits. Determine weather or not your home would benefit from the added moisture generated from the dryer and then make YOUR decision based on YOUR needs, not some blanket response. There are two things that are definite though. One is that this is only to be done with ELECTRIC dryers and the other is to have some form of lint filtration method employed which is a totally separate issue from the moisture issue and should be addressed independently from the moisture issue. I have NOT done the research on using this method on gas dryers simply because my dryer is electric but I am certain that if you have the time and money to invest in some sort of method to eliminate and natural gas from the heated air before you vent it into your home it most certainly exists. As far as the lint issue goes there are filters available down to .5 microns which will filter out the lint with no trouble but make sure you replace/wash them accordingly. There is actually a product designed specifically for this application. It’s called “Dryer Net” from demo air net. Here is the link. http://dryernet.com/ So that takes care of the lint issue provided you do what is required of you to maintain it. Then you can decide weather you need to address the humidity issue or if you would benefit from it. There are plenty of websites you can visit to help you determine how to check the humidity level in your home and what if anything you need to do to lower or raise it. Always consider any specific health issues when determining weather or not your home needs more or less humidity. What’s good for one person’s health may not be good for another, so make sure you take EVERYONE’S needs into consideration when making the decision. If you decide that you need to address the humidity situation before you vent the heat into your home then and in-line duct dehumidifier should take care of that as well. They range in price from around $200 to over $2,000 depending on what you need it to do but in the case of a dryer vent you should be fine with the $200 price range units available from most home stores such as Sears. In addition to these two products there are also in-line “air valves” that can control the air flow during those times you do NOT want the heat directed into your home. Simply install the in-line valve and when you want heat to be directed into the home you open the valve to the correct position to send the heat into the home or close the valve to direct the heat to your normal exhausting direction. Bottom line is YES you can safely and effectively use your dryer to heat your home provided you do a little research and determine what YOU need to do for YOUR specific application. In the process you can save yourself about $25 to $40 a month in heating costs thus paying for the items purchased and time used to install them over the long haul. Generally speaking if you save an average of $30 a month in heating costs by purchasing $240 worth of products the items will pay for themselves in only 8 months of usage. If you make use of your dryer for 4 months out of the year to help heat your home by the third year you will be putting money in the bank and we all love that. Hope this helps those of you who want an answer that isn’t a blanket answer offered by previous responders to this question. Not to knock them, they most likely simply did not consider all the variables in the question therefore answered off the hip versus actual research done on the products made to do this EXACT function. Good luck and happy heating. I’m staying toasty warm in my bedroom while my clothes are drying in the laundry room.