Draining Batteries

I started noticing a problem in the fall, my coach batteries would drain completely over a one week period. I ended up replacing the batteries as they were a few years old.
However this did not fix the draining issue, I installed a solar panel to keep the batteries topped up, this helps a little but there must be something using power. I switched the battery panel for the coach batt to OFF. I have looked for the obvious lights left on but have not found the culprit. I am guessing that it could be the power step, it has been acting strange since my last trip in the fall....
Re: Draining Batteries

My first thought would be the LP leak dectector, but you say you cut the coach batteries off. Make sure that is wired into the switch. The little light will go off if dead and you will hear a beeping when you throw the switch. I have seen them kill batteries in 3-4 days. Something must be running if you have good batteries.

DL Rupper

Senior Member
Re: Draining Batteries

Also check to see if you have a carbondioxide dector. They will drain the batteries also. They usally are wired direct to the coach batteries and you need to remove the fuzes on both detectors.
RE: Draining Batteries

Thanks for the replies, I am going to take another look at the LP system. I know it will end up being something simple....but it sure is annoying.
Re: Draining Batteries

Fridge may have a heater by the freezer door. Put in a disconnect on the battery... about a $5 item and rest easy.


New Member
Re: Draining Batteries

You may need to check each 12V circuit to find what's draining the battery. -- The fridge should have a heater switch ---


Senior Member
Re: Draining Batteries

A propane detector will drain a battery fairly quickly if it is one with the auto gas shut-off valve. That valve has power all of the time so it is a significant load. The type that just alarm also use some power, but it should take much more than a week to drain a good battery.

The CO detector would take several months to drain a battery as the power it draws when not alarming is in the miliamp range. One way to find the culpret is to connect an amp meter in series with one of the battery cables and the battery. Then you can start pulling the fuses to the 12V loads until you see the current drop to nothing. You will then know what caused the problem.

From reading your post it would seem that this problem was not there when you first began to use the RV but has shown up just lately. If that is true, look for something that has changed since it started to drain your battery. The electric step is usually wired to operate from the chassis battery, or at times from either the chassis or the coach battery. The reason is so that it will retract if you start the engine.
Re: Draining Batteries

I had the same problem. Not all of the 12v house circuits were tied into the RV battery switch inside the coach. I installed a battery discount switch in the battery bay and no more problems. Switch was ~$40.


Senior Member
Re: Draining Batteries

The battery disconnect is a good solution on older units. Some of the newer ones have a zillion computers in them which can get upset when deprived of power for a while.
RE: Draining Batteries

I was having similar problems with my Jayco travel trailer and finally ended up putting a battery cutoff switch on it. You can get these for $5 at Harbor Freight and I mounted it out of sight under the propane tanks.

What I found out was that even though you shut off the Master switch inside, the Carbon Monoxide alarm was still hot. I guess they wire it this way for safety reasons, but when I'm not sleeping in there, I don't care.

I park my trailer for a few months a year and it is in a location where someone (maybe kids) could possibly come by and play with the tongue jack switch. Not so bad but what if I have the stabilizers down? I wired this swtich to cut off everything.

Also, I bought a small trickle charger and leave it on all of the time. When I want to use my trailer, it's always ready to go. I read where it isn't good to let the batteries drain down and charge them before using it. I also installed a second battery in series for dry camping so I can watch a DVD movie before bed.