Reply
 
Thread Tools Display Modes
 
Old 10-27-2019, 12:50 PM   #1
Bus Crazy
 
Sleddgracer's Avatar
 
Join Date: Nov 2018
Location: south east BC, close to the Canadian/US border
Posts: 2,265
Year: 1975
Coachwork: Chevy
Chassis: 8 window
Engine: 454 LS7
Rated Cap: 24,500
alternative dehumidifying methods

I plan on winter camping in a converted school bus - average temperatures will be a minus 20 - 30 degree C - the steel body attracts condensation and propane heat adds moisture - electrical power is very limited - how practical would it be to use 165 lbs of silica gel to keep the moisture down compared to a very low powered dehumidifier? - the interior of the bus is approx 200 cu ft - one gram of silica gel will dehumidify 7'5 cubic feet - 55 lbs of silica gel sells for approx $200
Sleddgracer is offline   Reply With Quote
Old 10-27-2019, 01:26 PM   #2
Bus Crazy
 
Join Date: Nov 2016
Posts: 1,609
Useless.

Only use outside-vented heaters. For propane Propex HS2211 is good, but if your propulsion fuel is diesel then Webasto-style parking heaters are the bomb.

Very thick high R-value foam, very tightly sealed envelope are critical to per-day costs.

There should be zero thermal bridging, thus zero condensation.

Also doing without at night, or at least reducing the space heated.

But keeping ventilation going as well is (all that is) required against inside humidity, the "sealed envelope" just means you tightly control the CFM exchange rate.
john61ct is offline   Reply With Quote
Old 10-27-2019, 01:34 PM   #3
Bus Crazy
 
Sleddgracer's Avatar
 
Join Date: Nov 2018
Location: south east BC, close to the Canadian/US border
Posts: 2,265
Year: 1975
Coachwork: Chevy
Chassis: 8 window
Engine: 454 LS7
Rated Cap: 24,500
Quote:
Originally Posted by john61ct View Post
Useless.

Only use outside-vented heaters. For propane Propex HS2211 is good, but if your propulsion fuel is diesel then Webasto-style parking heaters are the bomb.

Very thick high R-value foam, very tightly sealed envelope are critical to per-day costs.

There should be zero thermal bridging, thus zero condensation.

Also doing without at night, or at least reducing the space heated.

But keeping ventilation going as well is (all that is) required against inside humidity, the "sealed envelope" just means you tightly control the CFM exchange rate.
this winter will have to be without foam insulation - even vented propane furnaces seem to add a lot of moisture to the air and I've found that mold can be a problem in our trailers - of course the trailers are heated 24/7 during the winter - they all need dehumidifiers - I'm trying to come up with an alternative to an electrically powered dehumidifier for the bus
Sleddgracer is offline   Reply With Quote
Old 10-27-2019, 02:48 PM   #4
Bus Nut
 
TJones's Avatar
 
Join Date: Jul 2017
Location: Rapid City, SD
Posts: 519
Year: 2001
Coachwork: Blue Bird
Chassis: CS RE
Engine: ISC 8.3 L 260 hp
Rated Cap: 36
Could you get a small air to air heat exchanger so you could bring in a little cold/dry outside air and warm it with the outgoing warm/humid air?

Or build a dehumidifier that uses cold air from the outside to cool and condense the moisture from the inside air?
The largest power consumption of a dehumidifier is the compressor for cooling it.

Ted
TJones is offline   Reply With Quote
Old 10-27-2019, 03:20 PM   #5
Bus Crazy
 
Sleddgracer's Avatar
 
Join Date: Nov 2018
Location: south east BC, close to the Canadian/US border
Posts: 2,265
Year: 1975
Coachwork: Chevy
Chassis: 8 window
Engine: 454 LS7
Rated Cap: 24,500
Quote:
Originally Posted by TJones View Post
Could you get a small air to air heat exchanger so you could bring in a little cold/dry outside air and warm it with the outgoing warm/humid air?

Or build a dehumidifier that uses cold air from the outside to cool and condense the moisture from the inside air?
The largest power consumption of a dehumidifier is the compressor for cooling it.

Ted
that would likely help and should be easy to rig up - a simple tin box built over the furnace exhaust vented to bring fresh air in from the outside - that would likely improve the efficiency of the furnace too
Sleddgracer is offline   Reply With Quote
Old 10-27-2019, 03:30 PM   #6
Bus Crazy
 
Join Date: Nov 2016
Posts: 1,609
Quote:
Originally Posted by Sleddgracer View Post
this winter will have to be without foam insulation
I think you must be talking about less cold environments.

I was specifically talking about the arctic conditions in your OP.

Increasing active cross-ventilation and raising temperatures are really the only alternatives.

Except moving to a drier location.

And forget American made RV-style heaters, the Propex and Webasto style are the way to go.

Also units designed for marine use.
john61ct is offline   Reply With Quote
Old 10-27-2019, 03:46 PM   #7
Bus Crazy
 
Sleddgracer's Avatar
 
Join Date: Nov 2018
Location: south east BC, close to the Canadian/US border
Posts: 2,265
Year: 1975
Coachwork: Chevy
Chassis: 8 window
Engine: 454 LS7
Rated Cap: 24,500
Quote:
Originally Posted by john61ct View Post
I think you must be talking about less cold environments.

I was specifically talking about the arctic conditions in your OP.

Increasing active cross-ventilation and raising temperatures are really the only alternatives.

Except moving to a drier location.

And forget American made RV-style heaters, the Propex and Webasto style are the way to go.

Also units designed for marine use.
I'm talking about northern BC, Alberta, and maybe Saskatchewan, perhaps even the Yukon and Yellowknife - so yeah, COLD weather - we survived much of the winter in those areas in an uninsulated holiday trailer with a tiny propane furnace, so I know it can be done - on the other hand I wasn't 60 yet and a lot tougher than I am now at 80+
Sleddgracer is offline   Reply With Quote
Reply

Thread Tools
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


» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 10:29 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
×