Converter does not run

[jalad12]

2019 Cougar 27Res. On my maiden voyage! Hooked up to a 50 amp circuit at a campground. Wired for 50 but have only one A/C unit. Things seemed ok for the first two days. Running A/C during day, fridge on electric, water heater on electric/gas, and toaster oven for toast at breakfast. This morning, the third day, voltage was 11.5 and steady. We left for several hours and returned to find voltage at 8.4. I checked the converter and The 35 amp fuse was blown. The 40 amp fuse was intact. I only had a 30 amp fuse to replace with and when I put the new fuse in the fan kicked on for about 5 seconds then shut off. I removed the fuse and checked it. It was still good. I put it back in and the fan again ran for 5 seconds before stopping. This cycle happened two more times before the fan didn’t come on at all. Do I need to charge the batteries before the converter will stay on ? Do I need a new converter? In the meantime, my slide outs won’t retract and I’m not sure if the auto leveling device will work. I’m supposed to be out of the campground in 12 hours!

[ChuckS]

Most likely you will need a new converter. I’d check connections at battery and make sure they are tight. New unit but stuff happens. I’m assuming g since it’s newnthe battery is hooked up properly. Go to any auto parts store and get right amperage fuse. Sounds like a thermal issue or sense issue with that converter.

You could also disconnect battery making sure to cover both leads. Then plug unit into shore power with proper amperage fuse installed and see if converter runs. Measure DC voltage and you should see around 13.4 to 13.8. If not fine your converter model number.... most likely a WFCO and use this trouble shooting tree


http://wfcoelectronics.com/wp-content/uploads/2015/11/New-Flow-Chart-for-WF-9800-Series.pdf

[ChuckS]

This should be what your converter on your model looks like

http://www.trekwood.com/products/1207785/Converter-Main-Board-Assembly-Complete-8955-ANP

It’s hard wired AC and DC intonthe connivence center. If bad I’d replace with and Progeessive dynamics model and you’ll just have to wire AC leads and DC leads to the new unit.

Much better convertor

[MattE303]

Even if your converter isn't working, you should be able to hook up the 7 pin from your truck so you can retract your slides and jacks. Keep the truck running and let it sit for a bit, that charges the battery but doesn't use the converter since it's 12v to 12v.

[identaltech]

I carry and battery charger just for times like this. Put it on the battery to keep it charged. The charger will take place of your converter. Keep camping and fix it when you get home. This has saved the weekend for multiple people camping with us.

[Canonman]

2019 Cougar 27Res. On my maiden voyage! Hooked up to a 50 amp circuit at a campground. Wired for 50 but have only one A/C unit. Things seemed ok for the first two days. Running A/C during day, fridge on electric, water heater on electric/gas, and toaster oven for toast at breakfast. This morning, the third day, voltage was 11.5 and steady. We left for several hours and returned to find voltage at 8.4. I checked the converter and The 35 amp fuse was blown. The 40 amp fuse was intact. I only had a 30 amp fuse to replace with and when I put the new fuse in the fan kicked on for about 5 seconds then shut off. I removed the fuse and checked it. It was still good. I put it back in and the fan again ran for 5 seconds before stopping. This cycle happened two more times before the fan didn’t come on at all. Do I need to charge the batteries before the converter will stay on ? Do I need a new converter? In the meantime, my slide outs won’t retract and I’m not sure if the auto leveling device will work. I’m supposed to be out of the campground in 12 hours!

My bet is the converter is ok. The batteries are, or at least one is bad. Each 12v battery is made up of 6 cells each storing 2.2vdc at full charge. If one cell is shorted the reading would be around 11vdc. The 35a fuse is probably the charging line back to the batteries. It likely blew due to the shorted/bad battery.
If you disconnect the batteries you can check the converter output by connecting to shore power as described earlier. If the lights in the trailer work and you're getting 13+ vdc at the main battery connection in the converter then the converter is OK.
With the batteries disconnected check the battery voltage of each, separately.
If one is in the 12v range hook it up. connect the tow vehicle cable to the trailer with the engine running and try your slides.
If neither battery is reading 12v. get/borrow another battery to operate your slides temporary until you get home and can have the batteries tested.
The slides are wired ahead of the converter so if the converter is bad it won't keep the slides from operating, but you must have a battery connected.

[Antelope]

We used a 5500 watt generator and replaced both 12 volt batteries but it won’t keep the charge is the converter bad and how much do the cost

[Antelope]

How much does a new converter cost

[Canonman]

Have you been able to test the converter? With either the generator or shore power the converter should be putting out 13+ vdc. You have a separate 35a fuse for charging the batteries. Is it OK? There is also a resettable fuse located at the batteries that can be blown. Do your 12v lights work?
In other words there is some troubleshooting I would do before changing the converter.
Converter is around $130 for the WFCO 8935 in our Cougar.

[bill-e]

I take it you don't want to go back to the dealer for warranty service? Others have given you good troubleshooting advise, at this point from what you've posted, you have not isolated the problem to the converter.

[Local150]

I had a converter go bad last week,, so I called the local dealer and he didn't have 1 but would order 1 a wfco 65 amp. 2 days later,, went to get it and he said 430 $,,, wth,, I can get one at CW for 215 and Amazon for 180,, I like to trade locally but,,,, damn

[ChuckS]

Tweety’s sells that wfco65 for 156. This is why I rarely buy locally. Not gonna pay markup prices.