Thread Tools Search this Thread Display Modes
Old 03-20-2009, 03:05 PM   #1
4 Rivet Member
outofcontrol's Avatar
1996 28' Excella
Portland , Oregon
Join Date: Jan 2006
Posts: 313
Blog Entries: 7
Battery and Univolt upgrade report - 1981 280 MoHo

1981 Airstream 280 Excella Motorhome.

  • Batteries won't hold a charge.
  • Univolt is annoyingly loud (buzzy).
  • Univolt is potentially bad for batteries.
  • I need to learn about battery maintenance.
Current equipment:
  • 2 - 12V Napa "Stowaway" marine deep cycle 27DC 180 reserve cap. min., 105 amp hours.
  • TU-570-6 Converter Charger (univolt?)
I went out to take some pictures, dimension measurements, and voltage readings last night. I turned on some lights for about 5 minutes while I looked around and uncovered the Univolt. By the time I got to the batteries, I noticed that the lights had dimmed, and my reading was 8.8 volts. I'm pretty sure that means my batteries are worthless.

I bought this RV 3 years ago as my first RV. I didn’t know how old the batteries were, and I didn’t really know what to expect from them. Even 3 years ago, we’d have to run the 6500w Onan Generator after a couple hours of running the heat, lights, and stereo. I thougt that was normal. I should also mention that we boondock 100% of the time when we use the RV. Afraid to admit that I needed to buy new batteries, we just ran the generator most of the time to supply power when we needed it. I recently sold the 6.5kw Onan on ebay for $550 and bought a Honda EU2000i for $865 (but that subject is for another forum thread). I also would plug the RV into shore power when I got home from every trip assuming that the converter/charger would magically maintain and charge the batteries. So, it would remain plugged in from 1 to 12 weeks until the next trip. 6 months ago I learned that this is poor practice, so I got a HD timer and set it to charge for 1hr 2x a day. I was expecting to find the batteries with no water in them from my abuse, but they were all full.

Plans for this upgrade:
  • Replace Univolt with a modern 3 phase charger.
  • Replace batteries with 2 6V and wire them in series.
What I’ve bought so far:
  • Ebay 260366399339 Intelli Power 12V, 60Amp 9260-C $128.70 (w/10% coupon)
  • Ebay 260366295455 Intelli Power Status remote Pendant $9.98
  • 2 Trojan T-105 6V Golf Cart batteries, $80 ea. (Craigslist.)
This new version of the Intelli-Power has a built in “charge wizard” and will be safe for me to leave plugged in while it’s parked next to my house. After some research, it seems like the 45amp version would work fine, but my current Univolt says 70amps, and for $30 more I thought I’d just be on the safe side and get the 60amp version. As far as the batteries go, I’d like to take Lewster’s advice and buy the Lifeline AGMs, but cost is paramount here, and these just happened to be available. There seems to be some debate as to what's better, and for my case; cost being important, lead is the way I'm going. Some guy bought 8 of them for a golf cart restoration project and never used them. They’re 8 months old, but have never been cycled. He’s kept them float charged on a shelf. I’m taking a chance on used batteries, but the balance between price is favorable. Plus he said he’d take them back if they didn’t work.

Future thoughts:
  • Now that I’ve traded out the massive 6.5kw Onan for the Honda EU2000i, I have some extra space to add 2 more batteries…that would be cool. CL guy has 8 if I want to buy more.
  • I’d like to upgrade the 12V distribution center to modern ATC fuses, but there’s not a problem with the original. (aint broke: don’t fix)
Sorry about the long post. My wife really doesn’t want to listen to me ramble on and on about this project, so I have to take it out here. J
I'll snap a shot of the batteries, looks like I forgot. (sorry about the poor quality, I took these with my cell phone)


1996 Airstream Excella 28'
2007 GMC Duramax 4x4 CCSB
outofcontrol is offline   Reply With Quote
Old 03-21-2009, 03:10 AM   #2
4 Rivet Member
outofcontrol's Avatar
1996 28' Excella
Portland , Oregon
Join Date: Jan 2006
Posts: 313
Blog Entries: 7
humm. don't know why some of my pics from the first post don't show up...

Came home today and the new converter was a day early on my porch. Installed it, no problems. let it run for about 15 min and then one of the AC breakers flipped. it's the 15 amp GFCI one. turned off some lights and it still won't stay on. I ran the extension cord from my garage straight to the new converter, and it works fine.

I think I did the math right, and this new converter should only eat about 8.5 Amps on full power, so I think I have a bad breaker??? or a bad power cord from the garage???

I knew it couldn't be that easy. it was just going so well.
Attached Thumbnails
Click image for larger version

Name:	Qphone509.jpg
Views:	144
Size:	52.8 KB
ID:	77204   Click image for larger version

Name:	Qphone510.jpg
Views:	122
Size:	39.3 KB
ID:	77205  

Click image for larger version

Name:	Qphone511.jpg
Views:	107
Size:	15.6 KB
ID:	77206   Click image for larger version

Name:	Qphone512.jpg
Views:	122
Size:	41.5 KB
ID:	77207  


1996 Airstream Excella 28'
2007 GMC Duramax 4x4 CCSB
outofcontrol is offline   Reply With Quote
Old 03-21-2009, 05:58 AM   #3
Site Team
azflycaster's Avatar
1975 25' Tradewind
Dewey , Arizona
Join Date: Mar 2005
Posts: 12,038
Images: 62
Blog Entries: 1
Several others have had this problem as well.
There seems to be issues with GFI circuits ant the new power supplies. Replacing the GFI breaker has fixed many. Moving the charger to a non GFI circuit is another option. I do not have any GFI breakers in my trailer and have not had this problem.


WBCCI President 2016-2017
azflycaster is offline   Reply With Quote
Old 03-21-2009, 04:13 PM   #4
4 Rivet Member
outofcontrol's Avatar
1996 28' Excella
Portland , Oregon
Join Date: Jan 2006
Posts: 313
Blog Entries: 7
I love great comments!

Excellent post! Thank you for the link! Exactly what I needed.

Home Depot had a 15amp for $3. and I bought a self contained slim mount outlet box for $6. There's some 110V wiring right there that is unused from the old Genset that I deleted, and it goes right to the 110V breaker box. I'm going to keep the rest of the coach on the original GFCI even if it's weak now (mostly since I haven't had a problem with it before, and a little because they are $40 to replace) and wire a new circuit dedicated to the new converter.

I probably could just replace the GFCI with a standard because I almost 100% boondock; so the only time I'm plugged in is to charge the batteries, but you never know what the future holds.

thanks again!
1996 Airstream Excella 28'
2007 GMC Duramax 4x4 CCSB
outofcontrol is offline   Reply With Quote
Old 03-21-2009, 07:22 PM   #5
4 Rivet Member
outofcontrol's Avatar
1996 28' Excella
Portland , Oregon
Join Date: Jan 2006
Posts: 313
Blog Entries: 7
After further research, I don't have a direct wire from the Univolt area to the 110V breaker box. I also found out that the bath, bath closet, 2 outlets over the 2 twins in the back and the univolt outlets are the only ones on the GFCI circuit.
don't really know why some are on the GFCI and the other half are not, but anyway, it was easier to just replace the GFCI breaker with a regular one. $3 fix.
1996 Airstream Excella 28'
2007 GMC Duramax 4x4 CCSB
outofcontrol is offline   Reply With Quote
Old 03-22-2009, 06:29 AM   #6
Rivet Master
bkahler's Avatar

1974 20' Argosy 20
Richmond , Kentucky
Join Date: Jan 2003
Posts: 5,150
If you haven't already, check the wiring in the breaker panel. When I replaced the univolt in our 310 motorhome I had the same GFCI breaker tripping problem. I bought a replacement breaker and when I went to install it I found that that the wiring was loose on the original breaker. Tightened everything down and its been working fine ever since.


Air forums # 1674
1974 20' Argosy Motor Home
1974 31' Excella trailer (parting out, as of 4/1/2015 I have wheels, brake drums, windows & holding tanks left to sell)
bkahler is offline   Reply With Quote

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
Performance report: Battery upgrade one year ago hshovic Electrical - Systems, Generators, Batteries & Solar 4 07-10-2009 09:04 AM
Classic MOHO Replacement Battery recommendations zamboni Classic Motorhomes 10 10-30-2007 06:28 PM
Univolt/Battery Help wingfoot321 Electrical - Systems, Generators, Batteries & Solar 11 04-14-2006 09:00 AM
Bambi upgrade to group 31 battery? rfield54 Electrical - Systems, Generators, Batteries & Solar 0 05-17-2005 09:33 AM
1981 Airstream Excella Univolt dienst1 Airstream Motorhome Forums 1 08-20-2002 09:05 AM

Virginia Campgrounds

Reviews provided by

Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities

Copyright 2002-2015 Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 06:39 AM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, Jelsoft Enterprises Ltd.

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