Batteries going dead in 24 hours with nothing on

[seasure1]

With everything off in the RV, what could drain down 2 brand new 31 series deep cycle battery and the starting motor battery in less than 24 hours.

I am at a loss

[Dwilcox]

Unless you disconnect the battery, everything is not truly off. Lots of vampire loads that will suck them down. Radios, LP detector, control boards etcetera.

[Bama Rambler]

You certainly have a load that needs to be found if it's draining down your batteries that fast. If you have a bad battery it will drain down the other batteries, but you said that the batteries were new. I would go ahead and have them load tested because you can get a brand new battery that's bad once in a while.

[bikendan]

Originally Posted by seasure1

With everything off in the RV, what could drain down 2 brand new 31 series deep cycle battery and the starting motor battery in less than 24 hours.

I am at a loss

I would think that a Georgetown MH would have a battery disconnect switch. Are you using it to prevent the parasitic power drains?

[Mrprovy]

We picked up out Geo Pro 16BH last weekend and had a similar problem. The camper was plugged in at the dealer all day, left the dealer at 5pm, speed to sleep at 10:30pm and turned the heat on. Woke up at 12:30am freezing; thermostat wouldn't click and lights we're very dim...batteries we're dead. Turned out the inverter was still on, and the outside refridge (120v basic dorm room fridge) that I was told only runs off shore power, was running off the inverter. Once home, shut the inverter, disconnected the fridge, and charged the battery over night. Battery held charge all week.

[seasure1]

appreciate everyone's response.

It happened with old batteries so I replaced all batteries

Checked inverter it was off.

Can't figure out what is putting on such a load.


Thanks for the suggestions!

[bikendan]

Originally Posted by seasure1

appreciate everyone's response.

It happened with old batteries so I replaced all batteries

Checked inverter it was off.

Can't figure out what is putting on such a load.


Thanks for the suggestions!

Modern RVs have numerous parasitic power drains. You still didn't say whether your MH has a battery disconnect switch or not.

[seasure1]

It has a power disconnect.

Here is the problem. We were dry camping and the batteries went dead with nothing on and the heater would not come on at 3:30 in the morning

[seasure1]

i understand about mystery draws on the batteries

Radio memory

LP gas monitor etc

This drain is much more than that

[TitanMike]

Originally Posted by seasure1

With everything off in the RV, what could drain down 2 brand new 31 series deep cycle battery and the starting motor battery in less than 24 hours.

I am at a loss

The starting battery going dead would lead me to suspect the isolator that allows house batteries to be charged while engine running but not allow starting battery to be discharged with engine off.

If this isolator is defective and leaves both coach and starting battery connected, a draw on EITHER battery will drain ALL.

If this isolator is the culprit it may be that you left something on like ignition switch, "parking" lights, etc.

My wife's favorite thing was to forget both the glove box and done lights and would leave them on until she was ready to drive her car again ------- a week or more later.

In your case I would make sure that coach and starting battery are isolated when engine is off. Then diagnose each system (House Batteries and items that run off starting battery).

[NXR]

Originally Posted by seasure1

It has a power disconnect.

Here is the problem. We were dry camping and the batteries went dead with nothing on and the heater would not come on at 3:30 in the morning

<scratching my head> Unless you set an alarm clock to wake up at 3:30 AM and manually turn the batteries on and light the furnace, something was on and monitoring the temps if nothing else.

Since they were old batteries than the cold could kill them.

Unless you have a mechanical battery disconnect switch, usually a giant knob, you do not have one. You can have a house battery on/off switch like I do but that is not a "disconnect" per se.

If you see any wires connected directly to your batteries with fuses in the wires, those are always either pulling power (like a propane leak detector) or are available even with the house battery off.

Ray

Ray

[Hclarkx]

Originally Posted by seasure1

i understand about mystery draws on the batteries

Radio memory

LP gas monitor etc

This drain is much more than that

Since you are dry camping and expecting the heat to come on, and the inverter is off, it's a 12V load item.

A tank heater or two might do the job. Non-LED outside lights or some such might (though you'd likely notice them on). A tank heater with a bad switch that says off but isn't? Will your fridge run on 12V? (most are 120 or propane, but I think some are 12V as well).

One bad battery could kill itself and a parallel battery. That energy would go into heat. Are the batteries warm when you find them discharged? Though a large load would warm them too if it's large enough.

Definitely need to find out why the ignition/starting battery is going down as well. Solving that problem might reveal the mystery load. I.e., the two problems may be related.

Anybody know what energizes the solenoid that joins the house and start/ignition batteries when the engine is running? I assume the engine must be running for that solenoid to close. I'm wondering if there's something awry in the engine system that's keeping that solenoid closed and running down the connected battery sets.

[gjarrette]

Originally Posted by seasure1

With everything off in the RV, what could drain down 2 brand new 31 series deep cycle battery and the starting motor battery in less than 24 hours.

I am at a loss

Did you by any chance pull the breakaway cable on the trailer when you disconnected from your truck? If you pull the brake away cable and pull the little pin out of its place in the break away switch your electric brakes will apply continuously and drain your battery. 4 wheels four brake actuator coils running and drawing power. 6 wheels 6 actuator coils running. Electric brakes have a coil which pulls the brake linings in to contact when brakes are applied or when the breakaway cable is pulled as in a run away trailer.

If you have an amp meter installed look at the amperage draw. If the pin is out reinstall it and look at the amperage.

[5picker]

Originally Posted by gjarrette

Did you by any chance pull the breakaway cable on the trailer when you disconnected from your truck? If you pull the brake away cable and pull the little pin out of its place in the break away switch your electric brakes will apply continuously and drain your battery. 4 wheels four brake actuator coils running and drawing power. 6 wheels 6 actuator coils running. Electric brakes have a coil which pulls the brake linings in to contact when brakes are applied or when the breakaway cable is pulled as in a run away trailer.

If you have an amp meter installed look at the amperage draw. If the pin is out reinstall it and look at the amperage.

The OP has a motorhome.
No breakaway switch.

[NXR]

Originally Posted by Hclarkx

Will your fridge run on 12V? (most are 120 or propane, but I think some are 12V as well).

Even propane ones require 12 VDC to run the control circuitry. Some pull as much as 3 amps from the DC source.

Ray

[Dwilcox]

And if you have a 12 volt fridge and it was on LP you may have a door heater that can draw down batteries fast. It is 12 volt. If you have a residential fridge was the inverter off?

[babock]

Put a meter measuring current between one of the battery cables and the battery. Then start pulling fuses to see what circuit is drawing current.

[camaraderie]

You need one of these to get to the bottom of the problem in a few minutes. CLAMP the red battery wire and read the DC amps drawn while using the coach and with "everything" shut off.
https://www.amazon.com/Auto-ranging-...%2C179&sr=8-36

If yer gonna boondock you really need a true battery monitor like the Victron.

[dcheatwood]

I was going to suggest as above that you put a meter on your batteries, pull all 12 volt fuses, then start putting them back in to see where the big draw starts.
Also,
Check things like fridge lights staying on when door is closed. Put cell phone inside in video mode and close for 10-20 seconds then watch video to see if light went out.
Check all lights in storage bays. Some are out of sight and hard to see except at night. My closets have auto-lights-on when open. I found one not going out due to latch not set correctly.
Check tank heaters.
It's a solvable problem but a real headache til it's solved. Best of luck and report with your findings. Thanks.

[Larry-NC]

Originally Posted by camaraderie

You need one of these to get to the bottom of the problem in a few minutes. CLAMP the red battery wire and read the DC amps drawn while using the coach and with "everything" shut off.
https://www.amazon.com/Auto-ranging-...%2C179&sr=8-36

If yer gonna boondock you really need a true battery monitor like the Victron.

You don't really need a clamp-on ammeter. Just put some heavy alligator clips on an ammeter and put it in series with one of the battery cables.

It is likely (not certain) that the draw is less than 10 amps. You could even use one of those giveaway Harbor Freight multimeters that has a 10 amp range. As you state, start pulling fuses and note how much current each one uses.