Reply
 
Thread Tools Search this Thread Display Modes
 
Old 05-11-2005, 11:04 AM   #1
Rivet Master
 
2003 25' Safari
Eden Prairie , Minnesota
Join Date: Nov 2002
Posts: 765
Images: 3
Condensation

On cool/cold nights when the trailer is closed-up we get a lot of condensation on the windows. One answer is to open a window or a vent, but that lets the heat out.

Our house has a device that brings cold, dry, outside air into the house, and blows warm, moist indoor air outside. It uses an air-to-air heat exchanger to transfer some of the heat energy from the outgoing air to warm up the incoming air. Does anyone know of a similar but much smaller 12 volt product for use in RV's? If not, is there a market for one?
__________________

__________________
Dan
dmac is offline   Reply With Quote
Old 05-11-2005, 12:36 PM   #2
Rivet Master
Airstream Dealer
 
Inland RV Center, In's Avatar
 
Corona , California
Join Date: Feb 2002
Posts: 16,499
Images: 1
dmac

Dan.

Some owners, use the AC in conjunction with the furnace.

The trick is to set the two thermostats so the furnace and AC don't fight each other.

Once those settings have been found, plenty of heat, with low humidity, will make you very comfortable.

Andy
__________________

__________________
Inland RV Center, In is offline   Reply With Quote
Old 05-11-2005, 12:38 PM   #3
Rivet Master
 
2003 25' Safari
Eden Prairie , Minnesota
Join Date: Nov 2002
Posts: 765
Images: 3
Having the AC cooling on a cold night while the furnace is heating seems a bit wastefull, and noisy. In my trailer a single thermostat operates both the AC and furnace, can't run both simultaniously. Also, what if you are operating in the 12 volt world?
__________________
Dan
dmac is offline   Reply With Quote
Old 05-11-2005, 12:47 PM   #4
Rivet Master
Airstream Dealer
 
Inland RV Center, In's Avatar
 
Corona , California
Join Date: Feb 2002
Posts: 16,499
Images: 1
dmac

Dan.

Special circumstances call for special methods.

When it comes to a persons comfort level, we all do things that are wasteful.
But if that makes us happy, then go for it.

Bring along a generator.

Your furnace should have a separate thermostat from the AC.

If not, they can be changed, so that they are.

Andy
__________________
Inland RV Center, In is offline   Reply With Quote
Old 05-11-2005, 12:51 PM   #5
2 Rivet Member
 
Join Date: May 2005
Posts: 64
Images: 3
Quote:
Originally Posted by Inland RV Center, In
Some owners, use the AC in conjunction with the furnace...
Doggone it! I thought I was being original when I started doing that!

It works quite well although it appears to annoy my wife with all the airflow.
__________________
joatmon is offline   Reply With Quote
Old 05-11-2005, 12:54 PM   #6
Site Team
 
, Minnesota
Join Date: Aug 2003
Posts: 6,940
Images: 59
Dan,

I couldn't find any ready-built, air-to-air exchangers with 12V fans that are smaller than 18" x 18" x 24".

What type furnace do you have? If you have a forced air system, you could add a bigger fresh air intake damper to draw in more fresh air, and immediately run it through the furnace. And add a small exhaust vent with a small muffin fan to get rid of part of the wet air.
__________________
markdoane is offline   Reply With Quote
Old 05-11-2005, 03:42 PM   #7
Aluminut
 
Silvertwinkie's Avatar
 
2004 25' Safari
. , Illinois
Join Date: Feb 2003
Posts: 10,334
Well, as I see it there are two options...stop breathing or deal with it....me I'm in the same boat as Dan and my choice was to live with it since I too can't have my A/C and furnace on at the same time...and Dan's right, it would be very noisy.
__________________
Computers manufactured by companies such as IBM, Compaq and millions of others are by far the most popular with about 70 million machines in use worldwide. Macintosh fans note that cockroaches are far more numerous than humans and that numbers alone do not denote a higher life form. -NY Times 11/91
Silvertwinkie is offline   Reply With Quote
Old 05-11-2005, 04:45 PM   #8
Rivet Master
Airstream Dealer
 
Inland RV Center, In's Avatar
 
Corona , California
Join Date: Feb 2002
Posts: 16,499
Images: 1
A glass of ice water, at a comfortable room temperature, will sweat on the outside of the glass.

Your Airstream trailer is the reverse. Cold outside, but warm inside. Therefore the windows will sweat on the inside.

Airstream attempted years ago to try and solve the problem with the double pane windows. Unfortunately, the double pane windows caused more problems than they solved and were discontinued.

Camping usually means we cannot have all the comforts of home. So as silvertwinkie said, "live with it", or "without it", as the case may be.

But you certainly can add it to one of the reasons why some wives won't go camping in the cold winter months. So guys, you will have to love with that, too.

Andy
__________________
Inland RV Center, In is offline   Reply With Quote
Old 05-11-2005, 05:00 PM   #9
Rivet Master
 
Join Date: Mar 2002
Posts: 1,482
Images: 19
We camp in some moderately cold weather - down to 30 or so, and find that leaving the bathroom vent cracked just open keeps condensation to a minimum without allowing too much warm air to escape. Of course, our coach is just 25', and there are only the two of us.

Mark
__________________
'85 Sovereign, 25'
j54mark is offline   Reply With Quote
Old 05-11-2005, 05:26 PM   #10
Site Team
 
, Minnesota
Join Date: Aug 2003
Posts: 6,940
Images: 59
If you buy some of those little dessicant sachets, they will keep the humidity down and reduce frosting of the windows. As a side benefit, as the dessicant absorbs water, they give off heat.

According to my calculations, you would need about 45,600 packets to be effective. Might be a storage problem. So I guess we'll have to love with that too!

My other idea to reduce the amount of respired moisture is to breathe into a plastic garbage bag. Every fifteen minutes, you tie the bag and place it outside the front door. In the morning all of your respired moisture will have frozen into ice, so you can dump it and reuse the bags.
__________________
markdoane is offline   Reply With Quote
Old 05-11-2005, 09:42 PM   #11
Aluminut
 
Silvertwinkie's Avatar
 
2004 25' Safari
. , Illinois
Join Date: Feb 2003
Posts: 10,334
Quote:
Originally Posted by Inland RV Center, In

But you certainly can add it to one of the reasons why some wives won't go camping in the cold winter months. So guys, you will have to love with that, too.

Andy
I don't see that as a problem.
__________________
Computers manufactured by companies such as IBM, Compaq and millions of others are by far the most popular with about 70 million machines in use worldwide. Macintosh fans note that cockroaches are far more numerous than humans and that numbers alone do not denote a higher life form. -NY Times 11/91
Silvertwinkie is offline   Reply With Quote
Old 05-12-2005, 10:44 AM   #12
Rivet Master
Airstream Dealer
 
Inland RV Center, In's Avatar
 
Corona , California
Join Date: Feb 2002
Posts: 16,499
Images: 1
Typos typos.

My last sentence in the above post, should have said "guys you will have to "live" with that, too".

Andy
__________________
Inland RV Center, In is offline   Reply With Quote
Old 05-12-2005, 10:50 AM   #13
Rivet Master
 
2003 25' Safari
Eden Prairie , Minnesota
Join Date: Nov 2002
Posts: 765
Images: 3
Back to my original question... I am thinking about:

- Buy a spare air-to-air heat exchanger core
- Cut the core on a bandsaw into smaller cubes, about 4" X 4"
- Attach two 12V computer muffin fans to a cube (one for intake, one for exhaust)
- Plumb it to provide the air exchange (for a test I could leave a window open, make a cardboard filler to block the open window with openings for intake and exhaust)
- And see if/how it works!

The trailer has a volume of about 1500 cubic ft. Using 20 cfm fans, minus 50% due to resistance, would completely change the air every 2.5 hours. Some housing codes specify .35 air changes per hour, or about 3 hours - so we are in the ballpark! 60 - 80% of the heat energy from the outgoing air is transferred to the incoming air. Two fans at .2 amps would consume 3.2 amps of power over 8 hours. On paper this all seems reasonable...

Perhaps it's an exercise in futility, as no one on the list seems too concerned about the condensation in their trailers. But it will keep me out of the bars for a few days
__________________
Dan
dmac is offline   Reply With Quote
Old 05-12-2005, 04:36 PM   #14
Aluminut
 
Silvertwinkie's Avatar
 
2004 25' Safari
. , Illinois
Join Date: Feb 2003
Posts: 10,334
Quote:
Originally Posted by dmac
But it will keep me out of the bars for a few days
LOL!!!
__________________

__________________
Computers manufactured by companies such as IBM, Compaq and millions of others are by far the most popular with about 70 million machines in use worldwide. Macintosh fans note that cockroaches are far more numerous than humans and that numbers alone do not denote a higher life form. -NY Times 11/91
Silvertwinkie is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
winterizing WINDOWS infinite LUX Windows & Screens 5 11-19-2003 05:48 PM
leak or condensation Tin Hut Windows & Screens 5 10-13-2003 04:42 PM
Window condensation Seon Windows & Screens 5 03-16-2003 11:19 PM
bed condensation kooblekidz Airstream Motorhome Forums 7 01-16-2003 09:52 AM
Window condensation????? Anna Windows & Screens 1 10-28-2002 11:51 PM


Virginia Campgrounds

Reviews provided by




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 07:59 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.