24V from Jayco 19RD WFCO-8955??

[boblanglois]

Hi, another head scratcher for me.

2014 Jayco 19RD with a WF-8955PEC converter. Has two Duracell Deep Cycle 12V in parallel. I have a cut-off switch and I disconnect from camper on Positive side when on shore power and use a battery tender to keep batteries topped up. Same setup I have had for years and no issues for years.

Just recently when I came back from a trip and stopped for a couple days at another home, I plugged into shorepower and no cutoff, so it was connected as it was originally designed to, with power converter charging batteries. My error, it was raining when we stopped and I forgot to follow standard practice. But for a couple days, I did not think it would have any real negative impact. As we were planning to leave, I noticed a sulfur smell, battery was warm/hot, and batteries were bubbling. I disconnected from shore power and brought it home.

At home, put my voltmeter on and when I plug into shore power, the voltage at the battery terminals starts climbing immediately up to 16V and higher (did not want to see how high so I shut off at 16V) and the bubbling starts immediately. When I disconnect from shore, it drops back down. I disconnected both batteries and brought them in the garage to add distilled water and put on a Battery Tender. Hopefully they are not permanently toasted.

With batteries removed, I then measured at the cables at front of camper with shore power on and get almost 24V?! I checked a couple times, same thing. Turned off converter breaker and back on, same reading. Next, I checked at my LP/CO detector: same reading (which is likely why that detector had started to act weird about the same time as we noticed the sulfur smell). Finally, popped the front cover off the converter and tried there, same reading, almost 24V.

So, what would make the converter suddenly start pushing out 24V instead of 12V and what can I do to fix or does the whole thing need to be replaced?

I reached out to Arterra (WFCO) but since out of warranty, I am not sure if they will give advice.

thanks

Bob

[skids]

Stupid question, but are the batteries hooked up in series somehow??

[boblanglois]

Definitely parallel. And they are not even in it now when I’m measuring.

[skids]

Run the batteries down to 12 volts with a 12V device that isn't too sensitive to overvoltage, like a 12V incandescent light. Then see how it acts to recharging to 12.8 Volts and with water levels at normal. Maybe you will get lucky.

[Nature Ist]

Have you researched known problems with converters putting out too much voltage? I would not use that converter connected to anything until you get it checked out. It sounds to me that your converter's voltage regulation has failed. I would be concerned about control boards on the refrigerator, hot water heater, etc being damaged by over-voltage.

[JimD]

Simple answer - if your converter is putting out 24 volts it is bad. No ifs, ands, or buts. If you look at the manufacturer's specs the voltage output range is a max of 14.6. It shouldn't matter whether a battery is connected or not.

You risk damaging any 12 volt appliance connected if it is putting 24 volts out.

[boblanglois]

Thank you for the quick replies. I have it shut off and hope it has not damaged anything else.

I see that WFCO makes a replacement MBA that looks simple enough to install but perhaps now is the time to upgrade to a better system? Any suggestions?

[ependydad]

Originally Posted by boblanglois

I see that WFCO makes a replacement MBA that looks simple enough to install but perhaps now is the time to upgrade to a better system? Any suggestions?

I've always been partial to Progressive Dynamics converters.

You might check to see what options there are at BestConverter.com.

[DaveT]

Originally Posted by boblanglois

I plugged into shorepower and no cutoff, so it was connected as it was originally designed to, with power converter charging batteries. My error, it was raining when we stopped and I forgot to follow standard practice.

Can you please elaborate what your "error" was and what is "standard practice" here you are describing?