Furrion 12 Volt Fridge Drains Battery on Shore Power

[xrated]

Nice clean job, very pro! Nice that you have heater control to protect your "babies" from freezing, lol. My batteries have the Daly BMS built in, they had a learning curve, but I like them now (2 batteries with each having a Daly). I have it set where it cuts the batteries off from charging at 2 degrees C. I also currently only keep mine at 14.2 VDC which seems to almost give me full capacity but is a bit gentler on the cathode rods inside the cells. So they claim. Glad you don't have the Smart Shunt, I was very disappointed in it. I have some other recent posts about my failures with it.

Thank you sir....I still have a bit of "clean up" work to do and I'm probably going to get rid of the double #6ga wires that feed from the Pos buss over to the OEM auto breaker group, and then the double#6ga wire from there to the 80A breaker for the hydraulic pump stuff. I'll replace it all with some #2ga welding cable and probably do some re-routing to neaten it up a bit.

I put four 7 1/2W 12V Facon heater pads in the box when I built it and it's completely insulated, so that should do it. I also ditched the OEM converter/charger too and bought a Mean Well NPB-750-12 and have it set on Lead Acid profile. It does 14.2V there and then floats at 13.4V, and just like you, to keep from stressing the LFPs at the top end. I load tested mine after I built it and got 305/306 AH out of them, with the Low Voltage cutoff on the BMS set to 2.55V per cell. I've since, upped it to 2.60V per cell and that should easily keep me off the bottom 10 to 12% of the battery.

I've yet to try the heated battery box...the weather had warmed up this spring before I had a chance to give it a test, but it's on my list of things to do when the weather turns cold again this winter. The way I've got it wired, I can feed everything heater related off of the Mean Well, as I'm plugged into 50A shore power here at the house, and leave the main battery disconnect open so it doesn't try to charge the battery until I make sure that everything is working correctly.

[trichwine]

So I guess we chalk this up to rookie mistake? If I had the battery disconnect in then at least my batteries would have gotten recharged at the same time that this 12 volt Furrion vampire fridge was sucking me dry to mitigate the draw down.

[TripleG]

Thank you sir....I still have a bit of "clean up" work to do and I'm probably going to get rid of the double #6ga wires that feed from the Pos buss over to the OEM auto breaker group, and then the double#6ga wire from there to the 80A breaker for the hydraulic pump stuff. I'll replace it all with some #2ga welding cable and probably do some re-routing to neaten it up a bit.

I put four 7 1/2W 12V Facon heater pads in the box when I built it and it's completely insulated, so that should do it. I also ditched the OEM converter/charger too and bought a Mean Well NPB-750-12 and have it set on Lead Acid profile. It does 14.2V there and then floats at 13.4V, and just like you, to keep from stressing the LFPs at the top end. I load tested mine after I built it and got 305/306 AH out of them, with the Low Voltage cutoff on the BMS set to 2.55V per cell. I've since, upped it to 2.60V per cell and that should easily keep me off the bottom 10 to 12% of the battery.

I've yet to try the heated battery box...the weather had warmed up this spring before I had a chance to give it a test, but it's on my list of things to do when the weather turns cold again this winter. The way I've got it wired, I can feed everything heater related off of the Mean Well, as I'm plugged into 50A shore power here at the house, and leave the main battery disconnect open so it doesn't try to charge the battery until I make sure that everything is working correctly.

You definitely put much thought and labor into your system. I think your heating pads/insulated box should work well. Nice that you can charge in below freezing temps. I myself don't cold weather camp and look to flee south in the winter months, but even down there it occasionally dips below freezing. So you have some capabilities that I don't have, plus an extra 60 amp hours. I like to keep my low voltage cutoff at 3.0V per cell. I know that is extra conservative and I would have no hesitation in dropping to 2.55V if I needed the juice. That is what is so nice about the Daly, that you can set up tight parameters and then relax them a bit if you need the extra power. If I ever built another system I would go the way you did and just assemble my own battery from Auto Grade cells. My batteries actually have 80 cells each that form up into 4 groups of cells that series up to finish the battery. Works well but I could have saved some money and maybe even netted 300 Amp hours like you have. The only thing I would do different in my system is get an inverter that actually makes 120VAC instead of the 111VAC that it puts out. It works and the sine wave is stable under load but I would rather just have 120 for all the electronic boards and appliances. It wasn't a high dollar one and may get replaced down the line. I replaced the converter with a WFCO 8955LIS it was an earlier mode prior to their auto detection model. It has just one minor peculiarity in that when I am off of shore power and I will open the main breaker, next, I open the converter breaker so I don't charge the batteries which are supplying the inverter. (endless loop). Finally I close the inverter breaker which is now the new AC feed to the AC load center and turn on the inverter. All works as expected, but when I draw high battery amps the converter fan will run like it is supplying the load which it is not. The DC amps would not even be passing thru the converter I believe by looking at your sketch. It isn't really noticeable but seems to me like it is a waste of battery when the converter is sitting off but somehow sensing either temp or higher amp draw. Still haven't wrapped my brain around this one and was just on their site looking for electrical diagrams to no avail.

[xrated]

So I guess we chalk this up to rookie mistake? If I had the battery disconnect in then at least my batteries would have gotten recharged at the same time that this 12 volt Furrion vampire fridge was sucking me dry to mitigate the draw down.

Yes sir, that is correct. Take it as a "lesson learned" though, and remember, you are no where near, not even close to being the first person that has done the same thing......some, repeatedly.

[trichwine]

Thanks. I’m at the campsite and it is overcast so the power situation isn’t getting better at the moment. It recovered to 77% on the drive here. I’m holding out hope that the $4K I spent on the upgrades will still get us through my mistake without having to resort to the generator, but at least we have one if needed.

[TripleG]

You definitely put much thought and labor into your system. I think your heating pads/insulated box should work well. Nice that you can charge in below freezing temps. I myself don't cold weather camp and look to flee south in the winter months, but even down there it occasionally dips below freezing. So you have some capabilities that I don't have, plus an extra 60 amp hours. I like to keep my low voltage cutoff at 3.0V per cell. I know that is extra conservative and I would have no hesitation in dropping to 2.55V if I needed the juice. That is what is so nice about the Daly, that you can set up tight parameters and then relax them a bit if you need the extra power. If I ever built another system I would go the way you did and just assemble my own battery from Auto Grade cells. My batteries actually have 80 cells each that form up into 4 groups of cells that series up to finish the battery. Works well but I could have saved some money and maybe even netted 300 Amp hours like you have. The only thing I would do different in my system is get an inverter that actually makes 120VAC instead of the 111VAC that it puts out. It works and the sine wave is stable under load but I would rather just have 120 for all the electronic boards and appliances. It wasn't a high dollar one and may get replaced down the line. I replaced the converter with a WFCO 8955LIS it was an earlier mode prior to their auto detection model. It has just one minor peculiarity in that when I am off of shore power and I will open the main breaker, next, I open the converter breaker so I don't charge the batteries which are supplying the inverter. (endless loop). Finally I close the inverter breaker which is now the new AC feed to the AC load center and turn on the inverter. All works as expected, but when I draw high battery amps the converter fan will run like it is supplying the load which it is not. The DC amps would not even be passing thru the converter I believe by looking at your sketch. It isn't really noticeable but seems to me like it is a waste of battery when the converter is sitting off but somehow sensing either temp or higher amp draw. Still haven't wrapped my brain around this one and was just on their site looking for electrical diagrams to no avail.

Just taking a peruse through the WFCO 8955LIS owners manual, looks like the converter fan is temperature controlled so it is running off temperature from the power being distributed through the load center so don't think I will find a way to stop the fans from intermittently running at high amp draws.

[TripleG]

Hopefully Mr. Sunshine will cooperate a bit with you and hit them panels! Enjoy your adventure!