Batteries ran down

[FTRVR]

Just purchased a 1997 Mountainaire. Hooked it up to shore power and left the battery disconnect in the use position and left some overhead lights on. Left it sitting for a couple of days and when I came back, both the house and chassis batteries had run down.

Had to jump start the engine and eventually got the generator started to charge the house batteries.

When hooked to shore power, should the disconnect be in the "Use" or "Store" position or did I do something else wrong.

Will be moving into it full-time this week and will be hooked up to shore power 99% of the time.

Please Help!!!!!!

[DandS]

Quote:

Originally Posted by FTRVR left the battery disconnect in the use position and left some overhead lights on. Left it sitting for a couple of days and when I came back, both the house and chassis batteries had run down.

Think you answered your own question. If you left some lights on for a couple days, that would be enough to run down your batteries. Leaving the disconnect in the use position by itself would not run down the batteries that quickly without some other current draw. If you're not using your coach for a few days it's probably wise to put it in store position.

[FTRVR]

So the shore power does not charge the batteries AND power the 12 volt lights?

[azloafer]

Quote:

Originally Posted by DandS Think you answered your own question. If you left some lights on for a couple days, that would be enough to run down your batteries. Leaving the disconnect in the use position by itself would not run down the batteries that quickly without some other current draw. If you're not using your coach for a few days it's probably wise to put it in store position.

My house and chassis batteries ran way down. I hadn't put the switches on store (real new at this) and the generator would not start. There is no electric where I store my coach. I managed to start the engine but not the generator. I have two questions:

#1: Does the generator start from the house or chassis batteries?

#2: When you have four house batteries how are the jumper cables attached to the batteries IF NEEDED to start the generator?

I've only had this coach long enough to camp out two weekends before my windshield popped out, but that is a separate problem addressed in another section of the forum. Please set me straight re batteries, I need your help.

[DandS]

azloafer - Usually the generator is started off the coach batteries but not sure about your setup. If you have (4) house batteries they are most likely wired parallel which means they are all tied together. Just attach jumpers to one positive and negative, doesn't matter which battery.

[CaptPat]

Quote:

Originally Posted by FTRVR So the shore power does not charge the batteries AND power the 12 volt lights?

On my coach shore power will maintain the batteries charged and run all the 12 volt loads and the 120 VAC loads, provided there is sufficient shore power available.

Since your lights were on that suggests that the battery disconnect switch is working, other things to check:

1. Was there power to where you connected for shore power?

2. Generator transfer switch. When the generator is running the transfer switch prevents shore power from entering the electrical system of the coach. The switch should shift the coach to shore power with the generator is turned off. Will the generator charge the batteries? If so at least part of the transfer switch is functioning properly.

3. Inverter/Converter this changes AC power from shorepower to DC for use for the 12 volt loads and the batteries. My converter has an on off switch, I'd check to make sure the converter was on there are probably some fuses or circuit breakers associated with the converter to check also.

Check for the simple stuff first, power, switches and fuses.

Hope this helps.

Pat

[DandS]

Quote:

Originally Posted by FTRVR So the shore power does not charge the batteries AND power the 12 volt lights?

It should! You did not state in your original post that you were hooked to shore power at the time. If you were, you have another problem - either your converter is not working or some other problem is present. If you have a voltage tester, check the output of the converter - it should read 13.5V or higher.

Edit: Reread your orig. post and you did state you were hooked to shore power - my error! Guess the eyes and the mind don't work too good anymore ? You need to do some additional checking as suggested by other posters.

[GaryKD]

Hi FTRVR,

My assumption is that your shore power is correct.

The disconnect switch needs to be in the "use" position if you want anything in the coach to work. The only thing different when charging the coach batteries via the generator or shore power is the converter/charger. Gut feel says the breaker powering the converter/charger circuit is tripped or the charging feature is not working on the converter/charger. The transfer switch could also be suspect. I do not know if a 1999 coach has an inverter.

1. Plug into shore power. Do you have 120 VAC available for high use appliances (microwave, HWH, W/D)? If so, the transfer switch is working okay.

2. Check the 120 VAC breaker panel. Is the breaker for the charger/converter tripped? If no then:

3. Check the input to the converter/charger. 120 VAC available? If yes,

4. Check the output side of the charger for 13.5 VDC or more.

5. If the VDC is available, move to the batteries and check for:
5a. If the batteries are flooded, is the water above the cells?
5b. Are all connections good and tight?
5c. Do you have 13.5 VDC at the battery terminal that the charger/converter connects to?
5d. If power is there, check the battery ground cables for a ground to the coach. Connections all tight? Also check with a meter.

6. If all the above is good, suspect the batteries are not accepting a charge. Disconnect the batteries from the coach and use a portable charger to fully charge them. Once fully charged let them sit for a couple of hours. Take a VDC reading. It should be 12.6 VDC (across the bank of batteries) or more. If no, the batteries are suspect. If okay, let them sit for a week disconnected from everything but each other. Take another VDC reading. The reading should be 12.6 VDC or more. If not, suspect the batteries. Take the batteries to your local auto supply store and have them give the batteries a load test. This will tell you the condition of the batteries.

Please let us know how all this works out or if you have additional ques tons.

[JVR]

I agree with Gary's assessment, and the most probable reason for the battery discharge while hooked to shorepower is the inverter was switched off.

Should you need to test the inverter output, be sure to disconnect the dc output cables before checking voltage, that way you will get a true output from the inverter and not influenced by a problem downstream.
JVR

[Jim Gibson]

My 93' Mountainaire use's the chassis batt. to start the gen.

[Robsons]

Hi all,

I have just had a very similar experience which may possibly explain the situation - although I'm not an electrical guy so I may have something wrong here.

- I had my coach hooked to shore power from my garage - 15 or 20A circuit
- My coach power panel showed that it was charging
- Someone left the bathroom lights on for 3 or 4 days before I noticed them.
- When I went to start the engine, I had a completely chassis dead battery - wouldn't even light up the instrument panel although my 12V lights everywhere else seemed fine although my battery boost button didn't give any real juice to help start the engine so the house batts must have been way low too
- While trying to figure it out, I noticed that my hard wired surge protector kept clipping out every time my garage lights went on (they turn on due to motion)

So, I know why my house batteries ran down: light was left on and I only had intermittent shore power which is probably very low current capable since it's from such a small source.

What I don't know is why my chassis battery went dead. I always thought that the chassis batt is electrically separated from the house batts so that you can run them all the way down and still be able to drive away the next morning.

My hypothesis is that because the RV's power panel saw that it was getting 120V from the garage that it opens a path to both sets of batts in order to charge them. This path allows the charges of all batts to be accessed by the bathroom lights that were left on AND the 120V source from the garage was not supplying enough energy to make up for the drain. Is this possible??

I'm most concerned that I don't run down my chassis batt and get stuck somewhere.

Dave