Battery Draining

Topic: Battery Draining (Read 883 times) previous topic - next topic

Battery Draining

December 07, 2015, 10:21:49 am

We just returned from Ft. Leavenworth, Kansas after attending our son's promotion ceremony to Major, (so proud!) I am having constant issues keeping the batteries from draining. It also draws down house batteries. I have to disconnect the negative lead on the chassis batteries every night or it will draw them down to nothing. Even with generator running, It will fault halfway thru the night. Any suggestions besides installing a battery disconnect switch? I plan to do that regardless. When the coach is running, voltage levels are 13 volts. Chassis Batteries are new and have been checked/load tested. Following Added: I have now discovered that this problem has taken out my Prosine Inverter/Charger so I am in the process of ordering new Magna 3000 Hybrid. A mere $2100.00 what fun! (Talked to previous owner. House batteries were 13 years old. Changed them out with new batteries and ordered new inverter/charger. Should solve my problem. Thanks for your replies.

Re: Battery Draining

Reply #1 – December 07, 2015, 10:38:49 am

Boost or other solenoid stuck on? Start hand testing for heat/warmth.

Pierce

Re: Battery Draining

Reply #2 – December 07, 2015, 10:44:45 am

Don't know where boost solenoid is located, but it does not light when depressed.

Re: Battery Draining

Reply #3 – December 07, 2015, 10:44:58 am

Especially if the boost solenoid was stuck "closed", there would have to be a substantial load connected to drain the batteries overnight.

HMMmmmmmm...(thinking really hard).

A short circuit would either trip a protection device (fuse, circuit breaker), or start a fire (heaven forbid), so not too likely...

(still thinking...)

Does this happen when plugged into shore power, or unplugged and running on inverter, or both?

Re: Battery Draining

Reply #4 – December 07, 2015, 11:10:09 am

Obvious that your isolation device is somehow bridged. Have another person stand in the bedroom while you activate/deactivate the boost switch. They should hear it click. On my older FT, the solenoid is near the batteries, under the entry steps, but over time, the location has migrated. Someone here should know where yours is.
As for the drain, check in closed compartments. I have a friend who had this exact issue, and spent a bunch of time and money trying to resolve it. Finally, he opened a bay door, and found a light bulb glowing. Spent several hundred dollars because of a $2 light left on.
But he got a lot of new equipment.

Re: Battery Draining

Reply #5 – December 07, 2015, 11:13:51 am

Quote from: mikeshort09 – December 07, 2015, 10:21:49 am

Even with generator running, It will fault halfway thru the night. Any suggestions besides installing a battery disconnect switch?

A disconnect switch is a good idea. I'm a tad confused (not enough coffee yet) about the "it will fault halfway thru the night" comment. You mean the gen set faults or your batteries drain? Good point about a simple light in the bay being left on.

Re: Battery Draining

Reply #6 – December 07, 2015, 11:15:56 am

Mike,

Chuck is probably correct. While the boost solenoid may get too hot to touch after an hour, it may not drain fast enough to flatten your batteries overnight. HMMmmmm, also still thinking.

You say the batteries are new. Possible installation problem/mistake? Did it also happen before the new batteries were fitted?

Boost solenoid switch on the dash may have a burned out bulb. OK, your solenoid is probably on your coach 12V bus panel along with the isolator, water pump relay, remote start solenoid, etc. You could carefully remove the positive cable from the isolator and then check overnight.

How about checking the current draw at the batteries? You could also drive it to a mom and pop electrical shop and for not much $$, they can figure out where the problem lies.

Solve the problem before putting in a disconnect switch. You NEED to know what is causing this.

Pierce

Re: Battery Draining

Reply #7 – December 07, 2015, 11:27:48 am

A '02 U320 (according to Beamalarm.com) has 3 gel 8D house batteries, and 3 D31 engine start batteries. If both those banks are (somehow) tied together, that is a lot of AMP-HOUR potential. I'm trying to figure what could drain that much power, and yet not be immediately obvious to the casual observer. Very puzzling...

Re: Battery Draining

Reply #8 – December 07, 2015, 11:38:31 am

Just a thought was each battery load tested individually?

Re: Battery Draining

Reply #9 – December 07, 2015, 11:56:40 am

I thought ALL FTs had a battery go/no go switch. Still in the dark (pun intended) about the OP's problem. I'm starting to lean towards a battery problem, rather than a short or something left on, tho that do happen!

Re: Battery Draining

Reply #10 – December 07, 2015, 12:40:50 pm

Your boost solenoid is probably under the foot of the bed, on the engine side.

Here are a couple of picture of mine, before and after replacement.

Hope this helps,

Trent

Re: Battery Draining

Reply #11 – December 07, 2015, 01:31:24 pm

Quote from: mike leary – December 07, 2015, 11:56:40 am

I thought ALL FTs had a battery go/no go switch.

The "Salesman Switch" is a convenience device used to turn off lights and electrical outlets inside the coach. What the OP is talking about is a "Master Disconnect" switch that would be located immediately adjacent to the batteries. Used to cut ALL power coming out of batteries.

Photo of the switch on our coach. The big red one...

Re: Battery Draining

Reply #12 – December 07, 2015, 01:38:17 pm

Just a thought,on my 96 the charging voltage should be set at 13.7/13.8,could it not be charging all the way.

Re: Battery Draining

Reply #13 – December 07, 2015, 01:54:32 pm

Quote from: Chuck & Jeannie – December 07, 2015, 01:31:24 pm

The "Salesman Switch" is a convenience device used to turn off lights and electrical outlets inside the coach. What the OP is talking about is a "Master Disconnect" switch that would be located immediately adjacent to the batteries. Used to cut ALL power coming out of batteries.

Photo of the switch on our coach. The big red one...

Is that an aftermarket battery disconnect switch?

Re: Battery Draining

Reply #14 – December 07, 2015, 01:57:53 pm

Quote from: Doug W. – December 07, 2015, 01:54:32 pm

That's not an aftermarket battery disconnect switch?

My thought, as well, sure looks nice & clean in there!

Will poke in ours under the cover on the right.

Re: Battery Draining

Reply #15 – December 07, 2015, 02:06:30 pm

Quote from: John44 – December 07, 2015, 01:38:17 pm

Just a thought,on my 96 the charging voltage should be set at 13.7/13.8,could it not be charging all the way.

Could be, ours, plugged in, with fresh batteries, shows 13.5 VDC. Our True Charge 40 shows nothing causing both banks to be charging, as it should, except for the usual coach draw & make-up, which is minor.

Re: Battery Draining

Reply #16 – December 07, 2015, 02:35:22 pm

Quote from: Doug W. – December 07, 2015, 01:54:32 pm

Is that an aftermarket battery disconnect switch?

Yes, they are sold by Blue Sea. Like all their products, it is top-of-the-line marine grade weather proof...a good one!

m-Series - Blue Sea Systems

Re: Battery Draining

Reply #17 – December 07, 2015, 02:36:41 pm

Susan and I are interested in this thread because we watch our various battery system monitors and end up mystified. For example:

When connected to shore power we'll see 13.7 to 13.9 for what we believe to be HOUSE batteries — seen on the battery/voltage monitor plugged into top 12V outlet on the dash. We have 3 new 8Ds, if that affects voltage we're seeing?

We saw 14.0 last week while on the generator.

As soon as we go OFF shore power, 13.7 to 13.9 drops to 12.8, yet the inverter/charger was not showing that the batteries were charging at that time. So, shouldn't the voltage reading have been constant?
Complicating our understanding of things, we have the old ProSine panel, not the ACS (2.5 or 3.0), which we would love to have, if anyone has one kicking around their garage.
Finally, our SeeLevel system monitor is in the bath, because we use it mostly for tank levels. However, the way it was installed, it is supposed to show ENGINE batteries' voltage. The SeeLevel seldom shows more than 12.8, although given its location, we don't look at it as often as the dash monitor for the house (we think) batteries. Maybe it shows 13's at times while charging?

Re: Battery Draining

Reply #18 – December 07, 2015, 02:52:06 pm

Quote from: LookingWest – December 07, 2015, 02:36:41 pm

...any pointers to resources (online class?) welcomed!

Three references from my collection of "handy links". They helped me understand how this stuff works...mostly.

Electrical Tutorial - Chapter 7 - Batteries and Chargers

Battery Basics: A Layman's Guide to Batte | BatteryStuff Articles

The RV BATTERY CHARGING PUZZLE « HandyBob's Blog

Re: Battery Draining

Reply #19 – December 07, 2015, 02:57:04 pm

Chuck & Jeannie,

Many thanks! Will check the out now. Sitting in customer lounge waiting for other (routine) coach maintenance, so this will be good study time. :-)

Re: Battery Draining

Reply #20 – December 07, 2015, 03:00:19 pm

Quote from: LookingWest – December 07, 2015, 02:36:41 pm

Susan and I are interested in this thread because we watch our various battery system monitors and end up mystified. For example: Clearly I need a class in coach battery power management, so, sorry for dumb questions.

Don't be sorry, we've all been down that road. There seem to be so many different charging systems on these coaches (some after market), that only a forum member who has the same system can be of help. Hang in there!

Re: Battery Draining

Reply #21 – December 07, 2015, 03:07:51 pm

Quote from: Chuck & Jeannie – December 07, 2015, 02:35:22 pm

Yes, they are sold by Blue Sea. Like all their products, it is top-of-the-line marine grade weather proof...a good one!

m-Series - Blue Sea Systems

Sorry Chuck the "OP" Threw me for a loop in your post showing the battery disconnect switch....Read it as other poster

Re: Battery Draining

Reply #22 – December 07, 2015, 03:47:19 pm

Quote from: Chuck & Jeannie – December 07, 2015, 02:35:22 pm

Yes, they are sold by Blue Sea. Like all their products, it is top-of-the-line marine grade weather proof...a good one!

m-Series - Blue Sea Systems

Just when I was saving some coach bucks, Chuck comes along with something that should have been stock!

Re: Battery Draining

Reply #23 – December 07, 2015, 03:52:39 pm

Mike,

You already have one. Under front of bed-- mechanical battery combine switch. OFF= alternator charges chassis battery only.
ON= both chassis and house banks charged by alternator.

ON also is a very high amp battery combine switch/duplicate of the boost switch.

Also, the Bluesea electronic switch for the ignition solenoid (rated for 1 million cycles and 450 amps continuous). Under left side of flip up dash.

Re: Battery Draining

Reply #24 – December 07, 2015, 03:56:35 pm

Is that the red household type switch on the foot of the bed?

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