Update in description. WFCO 9855-AD, 55 amp, Li or Lead Acid, Auto Detect Converter 9800 Series

[@tracyphillips3325]

Great review. Being automatic, between lead acid and lithium is pretty handy. Just in case you have to change back to lead acid.

[@FernbarkFrist]

They also have a unit with a manual switch on it if you want to go that way as well.

[@williamrizzo1285]

@Garage Kitchen of Science I am told WFCO no longer makes the manual switch version

[@pacificbushcraftandfirecra6358]

Great tech details Fernbark... Thanks for sharing.

[@FernbarkFrist]

Thanks for watching Brandon!

[@dubc3615]

Lots of good info for updating to be able to charge newer batteries. The cooling air room is interesting it would be hard to accommodate based on what you shown for the room. I can also see them requiring a certified installer to maintain warranty. They never seem to make it easy for DIY on this stuff.

[@FernbarkFrist]

There are many different levels of skill out there in the DIY'ers, so it is probably correct to have a certified person put it in.

[@RKCFALLC]

Just installed a WFCO 9855-AD in my fifth wheel. Luckily mine sits in the crawl space near the transfer switch so I had no size isses. I replaced a WFCO 9855 because I am switching over to Lithium batteries. Now the issue I had. I disconnected from Shore power and disconnected the batteries. Next I unplugged the converter. When changing out the red and black wires (12v output) The red wire was still hot, arced when I touched the case with my wrench. Where was it getting power from?

[@FernbarkFrist]

You will probably need to contact WFCO, but I am guessing there might be a capacitor in the old unit that was still hot, or you have another batter somewhere that is hooked up to your system.

[@glmorley]

Update: After setting the zero calibration on Victron BMV-712 and resetting history, the 9855-AD remained at 13.68 VDC/absorption mode for about 10 days while still plugged into house power. All good but a few days ago for some reason the Victron detected a load on the battery and reported the current draw and corresponding voltage reading of 13.1VDC for about 3-days. The 9855-AD began charging the battery and within about 24-hours was at 13.68 VDC and the Victron reported the LIfePO4 was 100% SOC.

[@Scott_Vicious]

That fan is a deal-breaker. Thanks for pointing that out. I'll give them a year to refine it hopefully.

[@FernbarkFrist]

This might not have been a production model. It did not come in a retail box, but I did watch another review about the same unit, and he noticed the noise too.

[@dustytravels9458]

And two weeks later.... WFCO Tech Support had me send my 9855-AD back in for a firmware update. Got it back two days ago, drained my 206aH SOK Battery down to 8%, installed the unit... NO Change ! Charging at a meak 12.5 amps. Left another message for Tech, getting really old.

[@dustytravels9458]

I installed the WF-9855-AD in my 2021 Grand Design Reflection after installing a SOK 206aH Lithium battery, but bulk charge is only 15amps for a short while, then drops off, and will only charge the battery to about 75% ???

[@FernbarkFrist]

It should charge it to 100%. It should stop when it detects the battery is at the charge voltage. Also, it takes a few discharge and recharge cycles for the charger to detect the correct battery chemistry.

[@dustytravels9458]

@@guywilliam6065 Appreciate the help, but after frying two of the WFCO units, I installed a PowerMax convertor at half the price 3 months ago and it's been purring along like a Kitten!

[@shovelhead8]

Looks like a pretty good unit. Any problem running this with a solar panel in parallel as well? Thank you for the review, Fernbark. Stay safe and stay warm

[@FernbarkFrist]

I believe that would not be a problem. I have solar gear just out of frame that I can hook up in a jiff.

[@glmorley]

Recently replaced my failed 9855 with new 9855-AD...charged 100Ah LiFePo4 at 14.4VDC while camping on shore power but now at home on house power and measuring 13.7VDC and battery is slowly draining. I don't think the WFCO is detecting the Li battery?

[@FernbarkFrist]

I think I would check to see if a gfci popped or a breaker popped. If you can't figure it out, give WFCO a call, they have been easy to talk to for me.

[@glmorley]

@@FernbarkFrist Thanks...breaker & fuses are good. Numerous calls into WFCO but sent to voice mail.

[@FernbarkFrist]

@@glmorley Wish I was more help, these things are really tough to trouble shoot if you are not on the scene

[@dustytravels9458]

Same with my upgrade ?

[@scarsman]

@@glmorley I have a brand new trailer with the 8740-AD. So far it hasn't detected and switched to lithium. Drained my batteries to 8%, and it charged in lead/acid mode. I've tried the power-off/power-on "trick" WFCO put out in a video to "force" it to switch to lithium, and that has not worked. After a week and a half of leaving voicemails and emails to WFCO with no response, I finally got an email response saying my batteries have to be run down until the BMS shuts them down before the unit will "auto-detect". As much as I don't really want to do this, I am currently running them down to try this. It is unbelievable to me that you have to go through this much hassle to "auto-detect". There's nothing "auto" about it if I have to completely kill my batteries to make it switch. This is something that would never happen naturally, so I am actually manually switching it to lithium mode by draining my batteries completely. Because this is somehow way more convenient than flipping a switch on the unit?????

[@tracyphillips3325]

Cool hat!

[@FernbarkFrist]

It's ok.

[@SmittyMRE]

One heck of a good design though, I tell you w-hat

[@tracyphillips3325]

@@SmittyMRE , one heck of a dude made that logo 🇨🇦

[@tracyphillips3325]

Hi Fernbark

[@FernbarkFrist]

Howdie