A/C circuit, batteries

jerryt253

Advanced Member
Joined
Jul 11, 2023
Messages
32
Location
Buckley
2013 Palazzo. Our second year in the RV world, still newbies, continuing to realize that there is a lot to learn, and always projects, which is good - keeps me out of trouble and continuing my education and learning. Very thankful for this Forum and the Participants willing to share their experience, knowledge and wisdom. I have found this forum to be much more helpful than talking to the folks at Thor Technical Support.

OK, first trip of the season just completed. Our coach had been in heated covered storage and hooked into 120v shore power since December. By the time we got to our destination (about 2 hours), red light fault indicator was on solid and our electric residential frig was no longer running. The message was 'bad battery'. On to 50amp shore power and all was good. Did not run the inverter on the trip home. Once home, plugged in 120v shore power. Called Thor and was told either bad batteries or bad isolator relay. Checked house batteries next day (4 - 6 volt, AH rating 235 (20HR) 190 (5HR) - not sure what exactly the two different AH ratings means. Indicator said batteries fully charged. I checked voltage and found the batteries at 6.24v, 6.34, 6.35 and 6.60 volts. As a test, I unplugged shore power and turned on inverter and frig. Less than 4 hours later, the fault light was back on as well as message displaying low battery (11.7v), frig not running. While driving, should the chassis battery not keep up with the minimal draw from the frig? Will I need to setup my AGS to maintain A/C current while driving between shore power or generator for boondocking? So, guessing that I need new house batteries, or?? I'm ok with replacing batteries but want to be certain the problem is batteries and not a relay. Oh, and also, the inverter fan never ran at all on this trip. It usually does come on after a trip.

If new batteries are needed, I will most likely go with AGM. Questions - 1) replace with 4 - 6 volt batteries or 2 - 12 volt? 2) Any changes needed for the charging/inverting system? 3) I am fairly mechanical, but would I do best to opt for 'professional' installation?

I thank you in advance for any advice or sharing of similar issues and solutions. So sorry for the long winded question.,
 
2013 Palazzo. Our second year in the RV world, still newbies, continuing to realize that there is a lot to learn, and always projects, which is good - keeps me out of trouble and continuing my education and learning. Very thankful for this Forum and the Participants willing to share their experience, knowledge and wisdom. I have found this forum to be much more helpful than talking to the folks at Thor Technical Support.

OK, first trip of the season just completed. Our coach had been in heated covered storage and hooked into 120v shore power since December. By the time we got to our destination (about 2 hours), red light fault indicator was on solid and our electric residential frig was no longer running. The message was 'bad battery'. On to 50amp shore power and all was good. Did not run the inverter on the trip home. Once home, plugged in 120v shore power. Called Thor and was told either bad batteries or bad isolator relay. Checked house batteries next day (4 - 6 volt, AH rating 235 (20HR) 190 (5HR) - not sure what exactly the two different AH ratings means. Indicator said batteries fully charged. I checked voltage and found the batteries at 6.24v, 6.34, 6.35 and 6.60 volts. As a test, I unplugged shore power and turned on inverter and frig. Less than 4 hours later, the fault light was back on as well as message displaying low battery (11.7v), frig not running. While driving, should the chassis battery not keep up with the minimal draw from the frig? Will I need to setup my AGS to maintain A/C current while driving between shore power or generator for boondocking? So, guessing that I need new house batteries, or?? I'm ok with replacing batteries but want to be certain the problem is batteries and not a relay. Oh, and also, the inverter fan never ran at all on this trip. It usually does come on after a trip.

If new batteries are needed, I will most likely go with AGM. Questions - 1) replace with 4 - 6 volt batteries or 2 - 12 volt? 2) Any changes needed for the charging/inverting system? 3) I am fairly mechanical, but would I do best to opt for 'professional' installation?

I thank you in advance for any advice or sharing of similar issues and solutions. So sorry for the long winded question.,

Sounds like your alternator is not charging the house batteries while you drive. Could be the BIRD is wired wrong (has happened from the factory on many units). Also possible the contactor that connects the two battery systems together has burned contacts.

Unplug from shore power and have the generator off. Put a voltmeter across the house battery bank and observe the voltage. Start the engine and wait about 5 minutes for the BIRD to close the contactor. If the alternator is charging the house batteries the voltage at the house battery bank should jump up above 13 volts with the engine running.
 
I agree with Bob about the alternator not charging the house batteries (it should) but not sure if you have a BIRD/Trombetta or a BCC. It is common for the Trombetta solenoid to fail.

However, I also agree that your fridge should not drain your 4 batteries in only 4 hours so they are probably due for replacement. Replace with 4 new batteries, either 6 volt or 12 volt (not two 12 volt).
 
Our rv is stored the same.
The batteries had a surface charge which shows a full charge but they discharge quickly. Ours finally got so bad they'd go from 8v to 14v on the charger in about 5minutes and discharge just as quickly.

Replace the batteries.
If you're going to keep the rv go to the last page of my signature thread and see the 12v100a lithium batteries on sale for $159.
 
Thank you all for your comments and suggestions. I will do testing first, as posted by Bob. Most likely and perhaps also - probably need a new set of batteries. I think AGM my best fit my needs.

Have a great day celebrating our great heritage, Independence and Freedom. May God save us from evil forces and Bless our Great Country.
 

Try RV LIFE Pro Free for 7 Days

  • New Ad-Free experience on this RV LIFE Community.
  • Plan the best RV Safe travel with RV LIFE Trip Wizard.
  • Navigate with our RV Safe GPS mobile app.
  • and much more...
Try RV LIFE Pro Today
Back
Top