Welcome to RVForums.com

  • Register now and join the discussion
  • Friendliest RV Community on the web
  • Modern site for PC's, Phones, Tablets - no 3rd party apps required
  • Ask questions, help others, review campgrounds
  • Get the most out of the RV Lifestyle
  • Invite everyone to RVForums.com and let's have fun
  • Commercial/Vendors welcome

Question Batteries not charging on shore power, is my converter bad

Welcome to RVForums.com

  • Register now and join the discussion
  • Modern secure site, no 3rd party apps required
  • Invite your friends and let's have fun
  • Commercial/Vendors welcome
  • Friendliest RV community on the web

brucewol

RVF Newbee
Joined
Feb 1, 2023
Messages
3
I've got a 2016 rockwood ultra 23 foot tt. it has a wfco wf-8955 converter in it. i first noticed the power center fan was coming on a lot more often. my batteries are old, so i just got 2 new 6 volt golf cart batteries. getting ready to install them but i'm suspicious that the converter is bad. here's what i've done

with batteries out, shore power on do not have 12 volts at battery terminals. fuses and disconnect switch at battery test good for conductivity. no obvious signs of damage to the wiring around the battery. checked the reverse polarity fuses and they are good.

inside , with shore power and no batteries, i have lights, water pump runs but not slide outs. so it looks like i've got 12 volts inside but only for low power. if i flip off the 120 volt breaker labeled conv, the lights go out. flip the breaker on, lights come on, the power center fan briefly comes on.

can my converter be bad but still provide low load power for things like lights but not charge the battery?

don't want to spend $200+ to throw a new converter at the problem. but not sure what else i can try. thanks for any help
 
The slides require more power than the converter will supply. The added power from the battery is required for proper operation of slides. This is the same for electric Jack's. I don't think you have a converter problem.
 
The slides require more power than the converter will supply. The added power from the battery is required for proper operation of slides. This is the same for electric Jack's. I don't think you have a converter problem.
Thanks Kevin - that makes sense, the converter can only provide low power but over a long time, it's enough to charge the battery. but I don't have 12 volts across the battery cable when the battery is disconnected. And the converter fan was coming on and staying on for a long time. I guess i can put my new batteries on, use shore power so the batteries should stay charged and monitor the voltage. My prior batteries were 7 years old so i can see why the failed even when on shore power with the converter. but the wf 9855 manual says i should have 12 volts with battery disconnected.
 
If its working it will show greater than 12v when charging (14.4v in bulk, 13.6v in absorption, 13.2 in float). So install your batteries and check the voltage with it on and off. The fan was probably running more because the converter/charger was working harder to keep seven year old batteries charged.
 
Also follow the wires, there are probably inline resettable fuses that are rectangular with posts. These can get weak and give poor contact.
 
Success!! I put the new batteries in. with the converter powered and battery disconnect engaged, I only had 12.7 volts at the battery, so not charging, I checked heavy wires at converter and had 13+ volts. after looking at the wiring of the converter, expected that as I had lights working inside and the heavy wires supplied the fuse panel. The jack now worked, again expected as it is wired to the battery disconnect and I have a good battery,

so it looked like the there was a break in the wiring between the converter and the battery. crawled around under the trailer and found a circuit breaker. Pushed in the reset plug and then checked the battery. now it as at 13.5, so was charging.

My prior batteries had failed and were putting a larger load on the converter. That's why the fan in the converter was running a lot more. The fact that I had lights meant that the converter was working. But the power wasn't getting to the battery. Eventually the bad batteries caused the converter to continually work so hard, that it tripped the circuit breaker. So I just needed to find, then reset the circuit breaker between the converter and battery.

Makes sense now. Thanks all for the tips that helped me understand the situation.
 
Thanks for the update and glad to hear things are working again.
 
The circuit breaker popped when the bad battery could not supply enough power. The converter runs most things and charges the battery but a good battery is needed for a large amp load.
Glad you found the problem.
 

Latest resources

Back
Top