Current leak in cold weather “cures” itself in warmer weather

[boyscout]

Like most GD trailers our 310GK leaks about 1/2 amp of 12V current at all times due to alarms and other devices that are always powered, even when the factory battery “kill” switch is turned off.

When circumstances kept us in cold northern temps until recently I noticed that this “no load” draw increased to as much as 2.1 amps - quadruple the normal draw. It seemed wise to investigate this new current leaking problem when we arrived in Florida rather than in the -16C temps at home.

Well, now we’re in Florida and the current draw has dropped back to 0.6 amps. I pulled each of the 15-amp fuses in the panel anyway, and the only one that made any difference was the fuse labeled for the black tank heater - current draw fell 0.2 amps when that fuse was removed. We’ve never turned on the black tank heater.

Any theories about what might be drawing a lot more power in cold weather, and why? Thanks in advance.

[Cate&Rob]

boyscout

Hi Mark,
I wonder if the tank heaters have some sort of "stand-by" power requirement when temps are low but the heaters are turned off? 0.2 A at 12V would be 2.4 watts . . . not enough to heat much. Another possibility is the propane detector. I wonder if it has to heat itself to some minimum temperature to operate correctly? Just a couple of guesses . . . no data to support.

Rob

[Country Campers]

I am no expert so please be nice.

Does a battery discharge faster at colder temps?

If one would have a loose or wet ground that would freeze in the colder temps would that "draw" more from the battery?

Brian

[Cate&Rob]

Does a battery discharge faster at colder temps?

Actually, it is the other way around. A lead/acid battery self discharge rate is reduced at colder temperatures.

Rob

[Kksfish]

Cate&Rob amp;

I wouldn’t disagree with the discharge rate being reduced in cold weather.....BUT why is it that contrary to anything that I have read my batteries will always fail on the coldest day of the year, at 11:00 at night, on a holiday!😂

Maybe it was always because I was driving a 20 year old clunker of some sort in those days or maybe it was just karma...

[Cate&Rob]

BUT why is it that contrary to anything that I have read my batteries will always fail on the coldest day of the year, at 11:00 at night, on a holiday!😂

Hi Keith,
You know . . . I have wondered the same thing . . . bin ther dun that . . . LOL

Rob

[Guest]

I believe a flooded battery at 100% capacity in warm conditions will lose 50% of its capacity at zero F. The self discharge rate is less but due to higher internal resistance, the capacity decreases. Dry cell batteries will maintain capacity at cold conditions. So a warm and weak flooded battery at 75F will exhibit half its capacity at 0F and your car will not start.

Jim

[Cate&Rob]

I believe a flooded battery at 100% capacity in warm conditions will lose 50% of its capacity at zero F. The self discharge rate is less but due to higher internal resistance, the capacity decreases. Dry cell batteries will maintain capacity at cold conditions. So a warm and weak flooded battery at 75F will exhibit half its capacity at 0F and your car will not start.

Jim

Hi Jim,

I believe that you statement is also correct. The difference is whether we are talking about self-discharge in storage or available discharge capacity in use. There is a great website on "everything" related to batteries. https://batteryuniversity.com/learn/...tery_knowledge This site discusses and compares all types of batteries, so you have to be careful that the graph you are looking at is about the type of battery you are investigating.

Rob

[Guest]

Great info Rob.

Jim