Reply
 
Thread Tools Search this Thread Display Modes
 
Old 08-23-2004, 10:27 AM   #1
Patriotic
 
Chuck's Avatar

 
1973 23' Safari
North of Boston , Massachusetts
Join Date: May 2002
Posts: 4,533
Images: 260
battery: phantom load, or normal discharge?

getting ready to go out dry-camping next weekend, so I was checking my battery yesterday. Voltage was down to 12.44. Trailer has been sitting for 2 weeks, not plugged in at all, not using anything since the last rally, where I was plugged into shore power for 3 straight days. as far as I can tell, the univolt works properly. I wouldn't think it would discharge that much in a couple of weeks. 2 things that I'm wondering:

1), I checked the water level, and it is high...possibly too high? water level appears to be up into the tubes.

2) my newer (<5 year old) fridge has been on the whole time, running on gas...wondering if these newer fridges are still using 12v for thermostat or other functions, even when set to "gas". (?).

I don't generally keep the trailer plugged in to a/c when not using it, (not anymore, anyway ), so as to avoid the dreaded univolt-overcharging syndrome.
__________________

__________________
Air:291
Wbcci: 3752
'73 Safari 23'
'00 Dodge Ram 1500 4x4 QC
Chuck is offline   Reply With Quote
Old 08-23-2004, 10:38 AM   #2
Rivet Master
 
TomW's Avatar
 
1967 26' Overlander
Huntsville , Alabama
Join Date: Dec 2003
Posts: 2,918
Images: 2
The easiest way to see if something is draining your battery is to make sure everything is off, then disconnect the positive lead from the battery, and put a 12 volt light bulb in series with the battery & the disconnected lead. The bulb should not glow. If it does, something is pulling current. How brightly it glows will determine if you have a problem.

Some of the electronics installed on everything (radio, fridge, etc.) may pull a tiny amount of current. However, I do not think any single one of the items would pull enough to illuminate the bulb.

Did you discover too much water in the cells before or after charging. I could see it being a little high after charging. Regardless, unless it was running out of the battery, I doubt the electrolyte being high would be a concern. But have no battery credentials.

Good luck!
Tom
__________________

__________________
TomW is offline   Reply With Quote
Old 08-23-2004, 11:59 AM   #3
Retired Moderator
 
john hd's Avatar
 
1992 29' Excella
madison , Wisconsin
Join Date: Aug 2002
Posts: 4,644
Images: 40
Quote:
2) my newer (<5 year old) fridge has been on the whole time, running on gas...wondering if these newer fridges are still using 12v for thermostat or other functions, even when set to "gas". (?).

chuck

does your fridge switch automaticly between 120 and gas?

if yes, i imagine there is a control circuit running.

also, are your batteries clean? dirty batteries will discharge faster than clean ones due to current passing from one post to another through the crud.

john
__________________
you call them ferrets, i call them weasels.
john hd is offline   Reply With Quote
Old 08-23-2004, 12:54 PM   #4
Patriotic
 
Chuck's Avatar

 
1973 23' Safari
North of Boston , Massachusetts
Join Date: May 2002
Posts: 4,533
Images: 260
Quote:
Originally Posted by john hd
chuck

does your fridge switch automaticly between 120 and gas?
no. manual switch: "gas", "off", "elec". however, if left on "gas", and there's no flame (as if you ran out of gas, or are just starting it on gas), the ignitor runs on 12v, and the "no flame" indicator clicks and blinks.

Quote:
Originally Posted by john hd
also, are your batteries clean? dirty batteries will discharge faster than clean ones due to current passing from one post to another through the crud.

john
they look clean to me. there's no crud trail leading from one post to the other. (battery is 1 year old).
__________________
Air:291
Wbcci: 3752
'73 Safari 23'
'00 Dodge Ram 1500 4x4 QC
Chuck is offline   Reply With Quote
Old 08-23-2004, 01:26 PM   #5
4 Rivet Member
 
Join Date: Aug 2002
Posts: 345
Quote:
Originally Posted by chuck
I don't generally keep the trailer plugged in to a/c when not using it, (not anymore, anyway ), so as to avoid the dreaded univolt-overcharging syndrome.
Chuck,

I definitely boiled out my batteries with the Univolt plugged in full time.

So I bought a heavy duty timer and plugged the Univolt into it and the timer into the wall socket (just made two short heavy extension cords) and then set the timer under the arm rest on the curb side.

Then I set the timer to run 1 hour a day while plugged in. When taking it out, I just set it to 'on' continuously.

Sure cured the boiling problem!!

Steve in Sav'h
__________________
Sav'h Steve is offline   Reply With Quote
Old 08-23-2004, 02:06 PM   #6
Rivet Master
 
ALANSD's Avatar

 
1966 26' Overlander
Woodstock , Georgia
Join Date: Feb 2002
Posts: 8,463
I use a blade switch on the battery post to disconnect it completely when sitting at home. I forgot last time to pull it and the digital clock drained the battery down over a few weeks. Also Optima batteries can take an almost complete discharge( down to 2volts or so) and be recharged with no loss of power or life expectancy. I put one in for my house battery.
__________________
1966 Overlander
AIR #005
Please visit our blogs and web pages:
OUR AIRSTREAM PASSION! BLOG
RESTORING AN AIRSTREAM
Our AIRSTREAM and TIN CAN TOURIST Rallys
ALANSD is offline   Reply With Quote
Old 08-23-2004, 03:38 PM   #7
3 Rivet Member
 
AirConditioner's Avatar
 
Join Date: Jul 2004
Posts: 152
Is the Univolt really outputting 12.8 vdc?

How did you check the Univolt? Is it at least buzzing?

It's possible it's not putting out any 12vdc (reads 24vdc unloaded on a digital multimeter). I had a situation where the Univolt was buzzing and outputing, but the fuse to the battery was blown. With this fuse blown and shorepower on it appeared that all was fine. When I dropped the shorepower, no power because the battery fuse was blown! Since this also prevents the Univolt from charging the battery, I was not aware the battery was slowly discharging over a period of about 30 days,

I installed a timer as well to assure Univolt plays nice with the battery. I'm exploring building a small trickle circuit to taper down the available charge to the battery from the Univolt.
__________________
AirConditioner is offline   Reply With Quote
Old 08-23-2004, 03:55 PM   #8
4 Rivet Member
 
sander17's Avatar
 
1996 28' Excella
Okemos , Michigan
Join Date: Apr 2003
Posts: 305
Images: 42
Chuck,
Check on the little lamps inside the storage compartments. They can get bumped on accidentally and if it is bright daylite, you may not notice. Good luck!
__________________
sander17 is offline   Reply With Quote
Old 08-23-2004, 04:56 PM   #9
Patriotic
 
Chuck's Avatar

 
1973 23' Safari
North of Boston , Massachusetts
Join Date: May 2002
Posts: 4,533
Images: 260
the voltage at the battery goes up when plugged into shore power, so I'm pretty sure the univolt is charging the battery. as soon as its plugged in, the voltage slowly goes up...I didn't check to see where it tops out. what should it be? I seem to remember someone posting what it should be in the past, and thinking that it was about where it should be. but I'll double-check.

there are no little lamps in any storage compartments. its an oldy...
__________________
Air:291
Wbcci: 3752
'73 Safari 23'
'00 Dodge Ram 1500 4x4 QC
Chuck is offline   Reply With Quote
Old 08-23-2004, 06:37 PM   #10
Retired Moderator
 
john hd's Avatar
 
1992 29' Excella
madison , Wisconsin
Join Date: Aug 2002
Posts: 4,644
Images: 40
Quote:
the ignitor runs on 12v, and the "no flame" indicator clicks and blinks.
chuck

wouldn't that be a 12 volt load?

john
__________________
you call them ferrets, i call them weasels.
john hd is offline   Reply With Quote
Old 08-24-2004, 08:36 AM   #11
Patriotic
 
Chuck's Avatar

 
1973 23' Safari
North of Boston , Massachusetts
Join Date: May 2002
Posts: 4,533
Images: 260
Quote:
Originally Posted by john hd
chuck

wouldn't that be a 12 volt load?

john
well, yeah. but is it on all the time, or only when you're trying to start the fridge on gas? is there a little brain in there doing some sort of "thinking" at all times..like the thermostat?

btw, I checked the voltage thismorning at the battery (plugged in to shore power): 13.5. that sounds like a reasonable charging voltage, yes?
__________________
Air:291
Wbcci: 3752
'73 Safari 23'
'00 Dodge Ram 1500 4x4 QC
Chuck is offline   Reply With Quote
Old 08-24-2004, 09:02 AM   #12
Moderator
 
jcanavera's Avatar

 
2004 30' Classic Slideout
Fenton , Missouri
Join Date: Mar 2002
Posts: 9,002
Images: 143
Send a message via AIM to jcanavera Send a message via Skype™ to jcanavera
We had a pretty good discussion about the draw down on my trailer as it sat in the storage lot. What's interesting is that with the master disconnect left on the sleeping electonics in the trailer and propane detector pretty much exhausted my battery within 45 days.

Here is the link to the thread with the details. I have yet to try this measurement on the Classic. http://www.airforums.com/forum...t=voltage+draw

Jack
__________________
Jack Canavera
STL Mo.
AIR #56
'04 Classic 30' S.O.,'03 GMC Savana 2500,'14 Honda CTX 700
jcanavera is offline   Reply With Quote
Old 08-25-2004, 01:13 AM   #13
2 Rivet Member
 
spinolio's Avatar
 
Join Date: Sep 2002
Posts: 64
Quote:
Originally Posted by ALANSD
I use a blade switch on the battery post to disconnect it completely when sitting at home. I forgot last time to pull it and the digital clock drained the battery down over a few weeks. Also Optima batteries can take an almost complete discharge( down to 2volts or so) and be recharged with no loss of power or life expectancy. I put one in for my house battery.
Seconded, I have the same setup except I never got around to replacing the house batteries with Optima Blue tops, I do however have a Red Top starting battery.
__________________

__________________
(no longer)on the road...
www.curtandmandy.com
spinolio 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
vintage airstream battery wildcat455 Electrical - Systems, Generators, Batteries & Solar 4 07-02-2003 01:50 PM
Battery Exploded wayner1239 Electrical - Systems, Generators, Batteries & Solar 15 05-11-2003 09:43 AM
Installing battery problem flyfisher Electrical - Systems, Generators, Batteries & Solar 2 04-01-2003 06:59 PM
Univolt with Battery Minder COArgosy78 Electrical - Systems, Generators, Batteries & Solar 32 03-10-2003 08:59 PM
igniton switch and the mystery of the dead battery Curtis-79MH Airstream Motorhome Forums 3 10-25-2002 03:58 PM


Virginia Campgrounds

Reviews provided by




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 08:26 PM.


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.