DIY ventilation heat exchanger - Page 3

Daox · 03-09-10, 03:09 PM

Yeah, it would be interesting to see what the European makers have done besides increase the size to get the extra efficiency.

AC_Hacker · 04-13-10, 03:17 PM

Quote:

Originally Posted by Piwoslaw

I found a (Swedish?) company that is a global supplier of heat exchangers:
Heatex AB

Piwoslaw,

Don't know if you saw it, but the company has some interesting ERV design software (more properly, sizing software). So if one were going to try to fabricate their own Energy Recovery Ventilator, You could get a good idea where to begin.

The link is here:

Heatex AB - The No.1 Air-to-Air Heat Exchanger Company: Thanks!

... If this doesn't work for you,maybe go to the root URL and look for "software".

Regards,

-AC_Hacker

Piwoslaw · 04-14-10, 12:23 AM

Thanx AC

Downloaded the program, now I'll have to find some time to play with it.

1blueox · 06-01-10, 05:06 PM

These are fascinating posts. Somebody asked about plans for 180 degree counter-flow exchangers so I thought I'd post.

I'm making a counter-flow air to air exchanger out of plywood and aluminum foil as an experiment. The design is very simple: imagine a piece of plywood as wide as the foil and as long as you want. Along the long edges are 1x2's to support the foil. Then the foil is laid on them. On top of the foil at its edges are another pair of 1x2's, with another sheet of plywood on top. Imagine folding the whole thing back on itself every couple of feet giving you two channels for the air, separated by foil (obviously you can't fold the plywood, that's just to give the concept). Add two small fans to move the air, some duct work at each end, and there you have it!

Those of you with far more experience than I have can improve on materials and dimensions, but if the foil is 18 inches wide and maybe 30 feet long, it should do a pretty good job. Humidity is not much of a factor where I live, but if condensation becomes a problem I'll clearly have to modify things a bit. This version is just for my own fun.

Xringer · 06-01-10, 06:10 PM

Sounds like an interesting experiment. Be sure to post some pics..

And welcome to the group..

Cheers,
Rich

Piwoslaw · 06-02-10, 12:02 AM

Hello 1blueox.
What kind of foil are you planning on using? I'm afraid that typical kitchen-grade aluminum foil is to flimsy and may not be able to handle the pressure differences between the channels it's separating. Aluminum that's slightly thicker than the kitchen stuff should be OK, you may also look around for thin copper foil, which is also a good heat conductor.

As for condensation, you'll get it anywhere that there is a temperature difference and at least some moisture in the air. The incoming air may have more moisture in the morning or during rain, the outgoing air will be carrying moisture from the house (showers, cooking, breathing). You'll have to make a small drain for both channels.

Daox · 06-02-10, 06:04 AM

Welcome to the site 1blueox. Sounds like a very interesting project. I too would love to see pictures as it progresses.

AC_Hacker · 06-14-10, 10:19 AM

1bluebox,

Quote:

Originally Posted by 1blueox

I'm making a counter-flow air to air exchanger out of plywood and aluminum foil as an experiment...

This sounds like a worthy project.

From my Internet research, it learned that there are two types of air energy recovery schemes. One uses non-porous membrane material, like aluminum foil, and the other uses a porous material that will allow condensing water to re-humidify incoming air. This might suggest other materials for you to try.

Also, it would seem to me that you'd want to go much thinner than 1x2 for your membrane separator. I'd think that membrane spacing on the order of 1/8 inch would be more in the ball park.

I also came across a DIY ERV discussion wherein someone was considering using a material like plastic food wrap for the membrane material. Seems like such a material would be cheap, easy to work with, quiet, and unaffected by condensation.

As my home insulation and infiltration project progresses, I'm beginning to notice that the controlled admission of new air is now required keep the comfort level at an acceptable level.

Regards,

-AC_Hacker

Xringer · 06-17-10, 09:26 PM

I saw some HRV units on Ebay in the $450 range. Looked up the maker and found this
site: HRV Airiva Heat Recovery Ventilator with a video.. http://www.suncourt.com/Flash/Suncourt%20Video.swf

Here's an installed review.. Amazon.com: Suncourt AIRIVA HE150 Heat Recovery Ventilation System: Everything Else

I've been thinking about air quality a lot lately. My wife has been experiencing
a hacking cough for years and it seems to be getting worse.
Doctors don't have a clue, so I'm wondering if it's airborne irritants.?.
Besides, I kinda like the idea of getting some fresh air during the winter,
when everything is shut up tight.

Daox · 06-18-10, 06:29 AM

Yeah, that looks about as efficient as the other ones I've seen. I'd like to see something ~90% efficient!

I'd try to open up the house when you can, try to get fresh air in. If that seems to help her you may be onto something.

03-09-10, 03:09 PM	#21
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	Yeah, it would be interesting to see what the European makers have done besides increase the size to get the extra efficiency. __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

06-01-10, 05:06 PM	#24
1blueox Lurking Renovator Join Date: Jun 2010 Location: Left Coast, USA Posts: 1 Thanks: 0 Thanked 0 Times in 0 Posts	A very home-made exchanger These are fascinating posts. Somebody asked about plans for 180 degree counter-flow exchangers so I thought I'd post. I'm making a counter-flow air to air exchanger out of plywood and aluminum foil as an experiment. The design is very simple: imagine a piece of plywood as wide as the foil and as long as you want. Along the long edges are 1x2's to support the foil. Then the foil is laid on them. On top of the foil at its edges are another pair of 1x2's, with another sheet of plywood on top. Imagine folding the whole thing back on itself every couple of feet giving you two channels for the air, separated by foil (obviously you can't fold the plywood, that's just to give the concept). Add two small fans to move the air, some duct work at each end, and there you have it! Those of you with far more experience than I have can improve on materials and dimensions, but if the foil is 18 inches wide and maybe 30 feet long, it should do a pretty good job. Humidity is not much of a factor where I live, but if condensation becomes a problem I'll clearly have to modify things a bit. This version is just for my own fun.

06-02-10, 06:04 AM	#27
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	Welcome to the site 1blueox. Sounds like a very interesting project. I too would love to see pictures as it progresses. __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

06-18-10, 06:29 AM	#30
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	Yeah, that looks about as efficient as the other ones I've seen. I'd like to see something ~90% efficient! I'd try to open up the house when you can, try to get fresh air in. If that seems to help her you may be onto something. __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

04-14-10, 12:23 AM	#23
Piwoslaw Super Moderator Join Date: May 2009 Location: Warsaw, Poland Posts: 964 Thanks: 189 Thanked 111 Times in 87 Posts	Thanx AC Downloaded the program, now I'll have to find some time to play with it.

06-01-10, 06:10 PM	#25
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	Sounds like an interesting experiment. Be sure to post some pics.. And welcome to the group.. Cheers, Rich

06-02-10, 12:02 AM	#26
Piwoslaw Super Moderator Join Date: May 2009 Location: Warsaw, Poland Posts: 964 Thanks: 189 Thanked 111 Times in 87 Posts	Hello 1blueox. What kind of foil are you planning on using? I'm afraid that typical kitchen-grade aluminum foil is to flimsy and may not be able to handle the pressure differences between the channels it's separating. Aluminum that's slightly thicker than the kitchen stuff should be OK, you may also look around for thin copper foil, which is also a good heat conductor. As for condensation, you'll get it anywhere that there is a temperature difference and at least some moisture in the air. The incoming air may have more moisture in the morning or during rain, the outgoing air will be carrying moisture from the house (showers, cooking, breathing). You'll have to make a small drain for both channels.

06-17-10, 09:26 PM	#29
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	I saw some HRV units on Ebay in the $450 range. Looked up the maker and found this site: HRV Airiva Heat Recovery Ventilator with a video.. http://www.suncourt.com/Flash/Suncourt%20Video.swf Here's an installed review.. Amazon.com: Suncourt AIRIVA HE150 Heat Recovery Ventilation System: Everything Else I've been thinking about air quality a lot lately. My wife has been experiencing a hacking cough for years and it seems to be getting worse. Doctors don't have a clue, so I'm wondering if it's airborne irritants.?. Besides, I kinda like the idea of getting some fresh air during the winter, when everything is shut up tight.