Solar water preheater/Dryer Vent

[w0ace]

Ok, so this is 2 in 1 I guess.....

First, I was thinking about just running some copper pipe in a frame on the roof painted black for solar preheater, running into the cold water inlet of the hot water heater.  I figure this will help out some as the tank will never see 58* water this way, and have to make such a big temp. rise.  Is this worth messing with??  Or will it not make that much difference?  

Next, I have been thinking about the dryer vent, seems like we waste alot of energy out the vent that we pay top dollar for.  Anyone got any good ideas what to use it for?  I was thinking about running tubing under my concret slab and vent the hot air thru it for warming in the winter time, but its really moist and I think that could cause problems, plus we don't use it that much!!  Anyone got anything on this??  Any ideas what to use it for??  Maybe heating the cold frame or small green house in the winter time a little extra??  That's all I could come up with.  

[Jimmy C.]

Check this out for dryer vent heating..
http://www.cetsolar.com/extraheat.htm

[w0ace]

Anyone used this before?  I was worring about the amount of water vapor in the air coming out from the dryer, I guess that will vary from start to finish....

[DavidLeBlanc]

One of the home improvement TV shows had an episode about a super insulated house whose only heating source was a heat exchanger on the hot water heater vent...

I think that house ended up being thought too (air) tight. Hopefully, things have progressed since then.

[Amanda_931]

Dryer heat?

Two things I'd wonder about--

Brown Lung is an evil disease--the cotton mill version of the coal miner's black lung.

Cotton dust, and I'd guess rayon dust as well,  is (are?) pretty flammable.  All fibers are likely to put dust into your rooms.

Sometimes only a dryer will do.  Works very nicely to get dog hair off a quilt (sponge it down and toss it in).  And if you have pollen issues--I do, and even though I'm not allergic to ragweed, too much of it does make me sneeze.  In other words, I'll probably get a dryer to supplement the clothesline.

But unless you live in a polluted city or a paper factory--or downwind from one, a clothesline is pretty wonderful--and a nice breezy day can dry your clothes in about the same time as most home dryers, at least the older ones.
  
For the slightly more permanent and sophisticated version of the old hippie solar water heater--black hose on the roof! I'd think it was a bunch more trouble than it's worth.  

More leaves, mold, pollen dust caught up on the roof.

We'd like to minimize holes in the roof--and the attendant possiblity of  leaks, particularly since these are not likely to take any of the standard store-bought flashings.

And if there's any possibility of a hard freeze up there....  

[glenn kangiser]

Amanda,

I caught my dog-- he wasn't liking it a bit -- was rather dirty  and as you mentioned had a lot of loose hair on him.  I sponged him down (thought I was gonna need stitches - he hates water) and I tossed him in the drier.

I used the normal cycle - lots of thumping and bumping - after about ten minutes I took him out, but he now seems a bit listless- :-/ do you think he will be alright - you're right it did remove most of his hair. What is the normal time for them to recover  Did I do it right or did I miss something

 Glenn

[jonsey/downunder]

Crikey Glenn, Didn't you read the instructions? You are supposed to wash them  on the wool cycle, drip dry and iron on a gentle setting, If you have a nice sunny day they may be hung on the cloths line by the ears, but only for short periods as they tend to sunburn and wrinkle in the heat. There is also the possibility of shrinkage, you could end up with a Chiwawa.
jonsey.

[Amanda_931]

Thank you Glenn!

 

[glenn kangiser]

My pleasure, Amanda.  Thanks for posting the cool way of removing dog hair.  Rover seems to have recovered nicely and none worse for the wear although he seems to have shrunk greatly as Jonesy mentioned.

I think he is now small enough that I may be able to use the microwave next time.

Anyone know how the microwave dried cat came out  (Don't try this at home kids, I'm just kidding around - fortunately most are urban legends.)
http://www.snopes.com/horrors/techno/micropet.htm

[John Raabe]

Filtration issues aside for a moment the main concern about reusing dryer waste heat is the moisture (which is what you are paying to remove in the first place).

If you are in a dry desert climate the moisture may be welcome in the heating system.

If, on the other hand, you are in a location like mine (Coastal Northwest) where indoor humidity in the winter never drops much below 60%, then adding moisture to the air can cause both small and large problems. Small problems include increased condensation on windows. Large problems include more hidden things like increasing activity of molds, mildew and certain bacteria that do well in warm damp environments.

The device I can imagine, but don't know if it exists, would have a heat exchanger with two completely sealed air chambers. The moisture laden dryer air would travel though one side giving up its heat to the other and condensing out the moisture to be recycled into the graywater system. The other side would preheat outside fresh air on its way into the house. After all, the dryer is pumping inside air to the outside in the first place.

One of the challenges of this device will be that the smaller the airflow chambers the better the heat exchange between the two airflows. But, the more likely it will be to clog up with lint.

Perhaps there could be some sort of self-cleaning air filter such as is now incorporated into most washers. (Remember when you used to have to clean the washer lint filter? - no more.)

[Amanda_931]

I think this was supposed to be simple.

There's an old Popular Science (or Mechanics?) article on a home-brew air-to--air heat exchanger--it looks a lot like some of the store-boughten ones.

I've got it in unmanagably large files.  But I could check to see what magazine and when.