Current leak in cold weather “clears up” in warm weather

[boyscout]

Like most GD trailers our 310GK leaks about 1/2 amp of current at all times even when nothing is turned on.

When circumstances kept us in cold northern temperatures I found that the “no load” current draw increased significantly to as high as 2.1 amps - four times the typical draw. Being a hardy northerner I resolved to look into the issue when we got to Florida rather than in the -16C temps we had at home.

Well, we’re in Florida now and the problem has “cured” itself, the “no load” draw is back to 1/2 amp. Nevertheless I pulled each of the 15-amp fuses in the fuse panel one at a time while monitoring current draw. The only one that made any difference - it dropped 0.2 amps - was the fuse labeled for the black tank heater. We’ve never turned on the black tank heater, but something in its circuit is drawing a little power even in warm Florida temps.

Anyone have any theories about what draws so much more current in cold temperatures, and why? Thanks in advance.

(For clarity, by “no load” I mean that the 12V system is enabled but nothing we turn on is turned on. Our factory battery “kill” switch has been replaced and properly kills everything - no current draw at all when it’s turned off.)

[JCR GD]

It sounds like your tank heater is working by itself. What does it draw when you actually turn it on?

[orbiker]

I'm guessing there is a damp or wet short to ground. Not enough to trip the fuse though. Maybe up in the insulation. KEN