Battery Drain

[ROOKSTOOL]

After about 8-10 days my primary battery completely drains. I can either use my emergency start (using the accessories battery) or I have to recharge my battery. Any recommendations as to why my battery drains when not in use?
Previously I would disconnect the negative terminal, but my battery still darins. Had the battery checked and it is still good. Now I have disconnected both terminals (+ and -).
Anyone else ever had that problem? Recommendations?

[blw2]

If you have disconnected either of the posts, then it sounds like a dead battery to me.

Sometimes one or more cells will die. The other cells are holding a charge so it seems like it's "ok", but then what happens is the good cells are continuously trying to charge the dead ones.... which is a loosing battle.

Have you checked your battery with a hydrometer?

Here is a good resource to learn about the care and feeding of batteries
The 12volt Side of Life (Part 1)

[mcr1010]

Most battery sales stores will check your battery by putting a load on it which will definitely show up a bad battery, usually free.

[ROOKSTOOL]

Thanks for your reply. I was surprised how short of life the battery in an RV has compared to a car.
I plan to take my RV to my local Advance Auto store to have it checked and replaced.

[blw2]

by short life, I assume that you mean because you are replacing it already.... and not because it needs recharging so often.

Actually, a good battery will last a very long time if used and maintained properly.

These things are usually equipped with a marine style "hybrid" battery, designed to be both a starting and deep cycle.... which really means it's not great for either application. Still, they are good enough for most folks use. If you are truly trying to use your RV off-grid, or dry camping as we say, then a true deep cycle will serve you better because the hold more capacity, and they also can tolerate deeper discharge.

A couple of things to keep in mind
1) even if you disconnect them completely while in storage, they will "self discharge" a few percent per month...meaning that if you let them sit unused for a few months in storage, they will be discharged as if it was used. A trickle charger is the answer here.... or keeping the RV plugged in so the converter keeps after it. Maintaining the fluid levels is important here too.

2) these wet cell batteries want to be stored charged, and do not take well to being drained or discharged too much. Some folks use a rule of thumb of don't discharge past 50%. Actually, some can take quite a bit more than this, but 50% is a good goal for most.
Even one discharge event down below this can cause permanent damage to the battery and will mean reduced capacity.


I think what happens with these new RV's is that they sit on dealer's lots for long periods of time. Salesmen and shoppers walking through might flip on lights, and forget to turn them off.... so they might sit with the light on till the battery is dead. It may take a bit of a charge so it seems like it's ok.... but then when someone buys it and starts camping, that is when the reduced capacity shows....

[DocMike]

blw2, what you said in the last paragraph is what I was told. Basically, the house batteries were not properly taken care of prior to my purchase of the RV and that is what lead to their short (5 mo) life after the sale. Since October 2015 my replacement Exide batteries have not missed a beat.

Bottom Line: If you have to buy the replacement batteries - you as the end user/owner - are being held responsible for how the unit was maintained prior to your purchase.

Doc

[Merv Tuttle]

Originally Posted by ROOKSTOOL

After about 8-10 days my primary battery completely drains. I can either use my emergency start (using the accessories battery) or I have to recharge my battery. Any recommendations as to why my battery drains when not in use?
Previously I would disconnect the negative terminal, but my battery still darins. Had the battery checked and it is still good. Now I have disconnected both terminals (+ and -).
Anyone else ever had that problem? Recommendations?

I had the same problem, it was a simple fix. I turned off the super fan in the bedroom area. I thought I had turned it off, but it was on low. And to my surprise it was wired to the battery under the hood. Once I turned off the fan the problem has gone away. Good luck.

[scrubjaysnest]

We had been keeping on eye on our cranking battery and starting the coach about every 7 days.
Had the idea to check drain on the battery and found the B.I.R.D draws a quarter amp. pulled the fuse and then next morning the battery was dead. Emergency start didn't work and the dash radio that I had pulled the fuse on was blinking after we did get the coach started. We used the gen set and a charger we carry to get the cranking battery back up.
End result was I added a 100 watt panel to keep the battery up until we get home this fall. At that time I will really getting into what is wired to what and how. Plans are to replace the house batteries with Exides and may change out the cranking battery. Will add a second charge controller and wiring with switching so a solar panel can be switched to the cranking battery as desired.