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BFL13's avatar
BFL13
Explorer II
Oct 27, 2017

More WFCO Woes

Friend with new to her 2008 Class C called saying while camping with grand-daughter and some dogs, with hook ups, the lights are dim and going dimmer back and forth.

So I as an rv.net trained "tech" am off to the rescue! :)

120v intake was ok, output at the converter was 11v sometimes 8v. Disconnected the single (new) 12v battery (voltage 10.6--yipes)

Lights in rig still work, so converter is working--but lights still going even dimmer at times then brighter. I have no clue how bright is normal with her rig. Still 11v and 8v at times, so converter has to be the culprit.

Attached my PowerMax adjustable voltage converter with wire clamps, set to 13.6v to battery wires in her rig. Ta da! Lights now very bright. Also now getting four lights instead of just three on the idiot light battery monitor.

Ok detached the PowerMax, installed a charged up 12v batt I took along just in case---lights still bright, re-attached the PowerMax at 13.6 and the lights went a little brighter. All is good!

So it seems the WFCO is having problems. It works with no battery and you get some voltage--11 or 8 so it seems like it is working but acting up a bit and the lights are really dim. BUT obviously the thing is not working right at 11v or 8v

So the plan is to get that WFCO out of there when she gets back and replace it.

I found it to be very confusing at first, that the WFCO was working with no battery so I suspected the battery, but the voltages were just too low and it kept dropping from 11 to 8 back and forth, with no battery at all, so it had to be the WFCO converter at fault.

(I have since recharged her battery and will get mine back and the PowerMax in a later swap)

19 Replies

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  • westend's avatar
    westend
    Explorer
    Oct 27, 2017
    Unfortunately you will be presented with too long a length of undersized wire which you will feel obigated to upgrade, and then the existing battery ring terminals will appear to have been inadequately installed by a meth addled gorilla with a hammer crimp with a fondness for elecrical tape which was first run through a sandbox and ...............
    "It's all in a day's work.." as they say. Might as well get her totally setup right (I'm sure BFL will do it).

    I've seen a few posts on WFCO repairs and recovery on this Forum. The bad news is that if a guy makes the standard repairs, you're still at the mercy of the poor charging design. A guy with a little electronic acumen may be able to enable a better charging profile with the exchange of some parts.

    Since reports of the WFCO's failing to produce 14+V for any suitable length of time so that batteries are charged fully and quickly (typical), The real fix may be to swap out IC's and components so that the charging schedule gets right.

    An alternative may be to bypass that regulation, pick a voltage, and make a failed WFCO into a fixed voltage charger.
  • landyacht318's avatar
    landyacht318
    Explorer
    Oct 27, 2017
    I have a nice finned heatsink and 80Mm addo computer fan from a failed Wfco from my neighbors RV. An Iota dsl-45 now resides there and two costco later GC-2s replaced some wally world 27s and he loves to tell me how well it works in comparison.

    The Wfco fan was too loud exhausting my electrical cabinet though, and a bit of an ampwhore, I replaced it with the Noctua NF-12 that was on my fridge condenser, when i put Noctua's latest 120MM fan(NF-A12x15) on the fridge condenser instead. It is said to outperform 2 NF-f12s in a push pull configuration.

    Thats all I can say about the Wfco, good for Recycled parts. I also use some of the flat steel inside of it as a ground plane for my Alfa wireless Wifi adapter.

    Will the vector charger handle usage as a converter? The smart chargers I presented with changing DC loads on a battery in the 80%+ charged range freaked out and shut down when loads got shut off.

    Your adjustable Powermax set to 13.6v, dont touch the dial, on full hookups, will perhaps eventually get battery full, and keep her in DC power, until the replacement converter arrives, and you then get to install that for her.

    Unfortunately you will be presented with too long a length of undersized wire which you will feel obigated to upgrade, and then the existing battery ring terminals will appear to have been inadequately installed by a meth addled gorilla with a hammer crimp with a fondness for elecrical tape which was first run through a sandbox and ...............
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Oct 27, 2017
    W/O Battery and good 120V AC the converter DC out S/B 13.2V DC MINIMUM

    YES the converter section is failing

    IF that WFCO is a 8900 series a PowerMax 55A is direct replacement
    WFCO 8900 Series (35,45,55) replacement


    Just did one for neighbor.
    Front panel comes off allowing access to lower section where converter is
    Couple of mounting screws.......5 wires (2 AC/2 DC/1 chassis grd)
  • BFL13's avatar
    BFL13
    Explorer II
    Oct 27, 2017
    MrWizard wrote:
    Nice to be able to help
    I think loaning her, one of the vector battery charger would he been better for her
    No chance of changing the voltage and damaging the battery


    Good point, but she won't mess up things. She is a respected judge for dog agility trials, so is very level-headed. One of DW's best pals, so I was sent off with no delay permitted. :)

    The tech interest would be how the converter was still actually working to a degree. Just not enough voltage. I suppose it would quit entirely eventually.

    Her fridge was not happy. With its door open it had a blinking light inside it. I didn't catch which brand of fridge. That stopped blinking once the voltage was back to what it should be. I didn't look at the fridge aspect, so no details on that.

    The battery compartment had a "battery control panel" with various fuses in it and some wires here and there. I had no clue what that was all about. Thanks goodness it didn't matter in this case.

    The WFCO inside the rig was just the breakers and fuses, with the converter behind the wall from that it in a separate compartment. The 120v for the WFCO was on the receptacle circuit but not sure how the converter was wired in. I think it must be hard wired, and not a plug in, from what I could tell.

    If I am sent to help with replacing it, I will learn more WFCOology later on.
  • MrWizard's avatar
    MrWizard
    Moderator
    Oct 27, 2017
    Nice to be able to help
    I think loaning her, one of the vector battery charger would he been better for her
    No chance of changing the voltage and damaging the battery

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