Hi,Very new to here and a recent purchase of a used '13 Jayco Swift SLX 154bh. I am having an issue with my converter. I have the WF-8735-P. Everything was working fine until I had a 30 amp outlet installed out side my house. The first time I plugged into the new outlet I heard a pop from the converter. The 30 amp fuse for the power keeps blowing. I disconnected from the battery and tried just plugging into the outlet, nothing. Battery still disconnect and used an adapter to plug into a standard house outlet, nothing. If I hook up the battery again and try to connect the fuse, I get sparks and the fuse goes again. I have now blown 5 fuses trying to track the issue down. Any help would be greatly appreciated.

Suspect yet another 30a outlet was installed with 240volts instead of 120v by an electrician with no clue about RVs.

My thoughts too. If this has happened you may have a damaged converter as well as some damaged appliances.

How would I check if the converter is fried?

Do not plug anything into that new 30a receptacle until you check it for voltage. You need a multimeter to do that. Plug the shore cord via adapter into a different 15a receptacle in your house (except not the bathroom GFCI one, which will add to the problem maybe) Disconnect the battery wires off the battery posts. Try your lights and fans. They should work on the converter's output. If you do have a multimeter, check the voltage at the converter's output (might need to use the DC fuse panel lugs for this) and see if it is 13.6ish. If it is only 12ish, you are on battery and not on converter.

Also, confirmed the following:30amp fuse blows anytime the battery is connected, even if no shoreline power.Yes, the electrician did have a 2 pole 30 amp breaker, 240v, initially.Now its 1 pole 120v.So, knowing this, am I to assume the converter is fried? If so, are they hard to replace? I am pretty handy, so I'd prefer to do it myself to save money.

WFCO converter keeps blowing 30 amp fuse | Good Sam Community

51 Replies

wa8yxm
Explorer III
Apr 22, 2018
Are you talking about a 30 amp fuse on the converter?>>> on a Blade type fuse on the 12 volt side of life.

The converter is 35 amps. the fuse 30.. There shoudl be a 2nd fuse or perhaps it was supposed to be a 40 amp. though I suspect a 2nd fuse.

Note if you have two fuses both must be replaced at teh same time with the converter OFF during replacement.. For at least 30 minutes.

Another thing that can turn that fuse(s) into Pop-a-matics is reverse install of the battery.

They are after all called "Reverse Polarity Fuses".
drsteve
Explorer
Apr 22, 2018
tylrphx wrote:
Hey Guys. I made the mistake of connecting my battery in reverse. I was expecting the fuse to blow but it did not. I replaced the 40 AMP protection fuse on the WF-8735P but no luck. Dealer service told me it was a fried Converter. I just bought this Jay Flight SLX 154 last month. it's a 2018. I made note of all of your suggestions in this thread. While I am confident I can replace the part described earlier, will that void any other part of my warranty? Thanks in advance.

You will get more responses if you start a new thread. Just above the list of existing threads it says "Post New Topic". Click there, and post your question. And welcome to the forums!
tylrphx
Explorer
Apr 22, 2018
Hey Guys. I made the mistake of connecting my battery in reverse. I was expecting the fuse to blow but it did not. I replaced the 40 AMP protection fuse on the WF-8735P but no luck. Dealer service told me it was a fried Converter. I just bought this Jay Flight SLX 154 last month. it's a 2018. I made note of all of your suggestions in this thread. While I am confident I can replace the part described earlier, will that void any other part of my warranty? Thanks in advance.
scubadvr
Explorer
Feb 12, 2018
I've spent a good hour with the cover off. Only found one fuse, tested and appears to be good. But I will get another tomorrow to confirm.

Thanks again for all the help.
Lynnmor
Explorer
Feb 11, 2018
I did an autopsy on a dead microwave. When I unwound the windings in the transformer, I found a blown fuse buried deeply. I don’t believe it was heat protection, rather just a way to hose the consumer.
MEXICOWANDERER
Explorer
Feb 11, 2018
BOTH fuses are inside the microwave

Remove entire microwave from it's mounting
Remove the cover
The screws may be SECURITY type TORX. You will need a specific tool to remove them
USE CARE when digging around on the circuit board
High voltage capacitors can retain annoying amounts of zapping power
Not a hazard unless you like jabbing your fingers haphazardly
You are looking for glass tubular fuses similar to old-fashioned car fuses
With strong lighting and reading glasses look at the center fuse element
Is it broken or is the fuse glass blackened?
Replace both fuses if faulty
Bench test with cover off. If good, blow dust and grime off the circuit board with compressed air and install
It is not evil to rescue an appliance and save $100+
scubadvr
Explorer
Feb 11, 2018
MEXICOWANDERER wrote:
Many microwave ovens have 2 fuses -- one for power 2nd for controls

Would the 2nd fuse be inside the MW? I've pulled it out, and tried it in the house as well with no luck.
Bobbo
Explorer II
Feb 11, 2018
If all you lost is the MW and the converter/charger, you were pretty lucky.
MEXICOWANDERER
Explorer
Feb 11, 2018
Many microwave ovens have 2 fuses -- one for power 2nd for controls
scubadvr
Explorer
Feb 11, 2018
Update. Installed new Progressive Dynamics PD4135. All wiring appears to be good. Other than frying the converter, looks like the microwave is done too. Fridge and AC are good. Think I am pretty lucky.