Battery Drain Puzzle

[dbaur]

We have a 7 month old 2016 Classic. The battery drains to 70-75% even when we are plugged into a 50 amp connection at a campsite. Usually due to solar and/or towing the level goes back to 100% during the day. We have had the camper looked at twice at an Airstream Dealer and they tell us our electrical system is fine. Has anyone else had this problem and what could be the cause and cure? Appreciate some help with this. Thank you.

[OTRA15]

When you are plugged into shore power, what is the voltage readout on your monitor? It should be 13.7 volts plus or minus, for regular wet cell lead acid batteries. Not sure where you got the percentage figures, but the actual voltage readings are better to work from IMO. Make sure your Use/Store switch is in the Use mode, which is required for the batteries to be charged.

If you disconnect from shore power, and wait an hour, turn off all 12-volt functions like lights, water pump, and so forth, then tell us what the battery voltage is on your monitor panel. It should be about 12.7 to 12.8 volts.

Without reconnecting shore power, use the trailer normally for 4 hours or so [lights, water pump, radio, TV, etc.], then turn off the 12-volt functions, and report on the battery voltage at that point. It should be lower, but still above 12.5 volts.

These first steps will help us get to a better understanding of what is going on. If your voltage is below 12.5 you should plug back into shore power. If the battery voltage drops below 12.2 volts in the 4 hours, there is indeed a problem IMO.

Your reading of 70-75% does not sound right IMO.

Good luck!

Peter

PS -- This Battery School resource is good background reading on RV batteries and the charging system:

http://www.batteriesnorthwest.com/ba...hool.cfm?TID=0

PS2 -- Do you have AGM sealed batteries?

[uncle_bob]

Hi

Unless you are running a fancy after market battery monitor, you are simply looking at a device that guesses the battery charge based on voltage. If you have significant loads (like the inverter) that will fool the monitor.

If the battery really is regularly going down to 75% charged, that's half of the useful capacity of the batteries. You never really want to go past 50%.

Since you mention solar, I'm assuming you have the factory solar package. I believe that also means you have AGM batteries. They should clock in around 200AH fully charged. 25% of that would be 50AH. Something around a 4A load would take them that far down in 12 hours. 2A would do it in 24 hours. If the inverter is turned on all the time, that would do it.

When plugged into shore power, the converter should charge the batteries. If it's not doing so, something is wrong. If they are discharged, it will take a while (like 24 hours) to get them back to "full" with a working converter on shore power. I'd check the converter to make sure it's running. I'd also check the state of the "store / use" switch to be sure it's in "use".

Lots of things to dig into ....

Right now:

1) Do you run the inverter?

2) What's the state of the store / use "disconnect" switch?

Bob

[TG Twinkie]

I don't care what the dealer says. The converter is not charging the batteries.
When you are plugged in to shore power the batteries should not drain at all. The converter will provide all the 12 volt power you need plus keep the batteries charged.
In my limited experience with dealership technicians. Most are "remove and replace" not trouble shooters.
Like you would do with doctors. GET A SECOND OPINION.

[dbaur]

We are currently plugged into 50 amp shore power. Both the See Level II and the Sun Explorer monitors are showing 12.3 volts and 75% battery remaining. The Surge Protector reads normal. We are in the "use" mode. What could be going on?

[dbaur]

Originally Posted by uncle_bob

Hi

Unless you are running a fancy after market battery monitor, you are simply looking at a device that guesses the battery charge based on voltage. If you have significant loads (like the inverter) that will fool the monitor.

If the battery really is regularly going down to 75% charged, that's half of the useful capacity of the batteries. You never really want to go past 50%.

Since you mention solar, I'm assuming you have the factory solar package. I believe that also means you have AGM batteries. They should clock in around 200AH fully charged. 25% of that would be 50AH. Something around a 4A load would take them that far down in 12 hours. 2A would do it in 24 hours. If the inverter is turned on all the time, that would do it.

When plugged into shore power, the converter should charge the batteries. If it's not doing so, something is wrong. If they are discharged, it will take a while (like 24 hours) to get them back to "full" with a working converter on shore power. I'd check the converter to make sure it's running. I'd also check the state of the "store / use" switch to be sure it's in "use".

Lots of things to dig into ....

Right now:

1) Do you run the inverter?

2) What's the state of the store / use "disconnect" switch?

Bob

We do not run the inverter and the "use" switch is on. Voltage shows 12.3 on both monitors and we are plugged into 50 amp shore power?? Any ideas?

[dbaur]

Originally Posted by OTRA15

When you are plugged into shore power, what is the voltage readout on your monitor? It should be 13.7 volts plus or minus, for regular wet cell lead acid batteries. Not sure where you got the percentage figures, but the actual voltage readings are better to work from IMO. Make sure your Use/Store switch is in the Use mode, which is required for the batteries to be charged.

If you disconnect from shore power, and wait an hour, turn off all 12-volt functions like lights, water pump, and so forth, then tell us what the battery voltage is on your monitor panel. It should be about 12.7 to 12.8 volts.

Without reconnecting shore power, use the trailer normally for 4 hours or so [lights, water pump, radio, TV, etc.], then turn off the 12-volt functions, and report on the battery voltage at that point. It should be lower, but still above 12.5 volts.

These first steps will help us get to a better understanding of what is going on. If your voltage is below 12.5 you should plug back into shore power. If the battery voltage drops below 12.2 volts in the 4 hours, there is indeed a problem IMO.

Your reading of 70-75% does not sound right IMO.

Good luck!

Peter

PS -- This Battery School resource is good background reading on RV batteries and the charging system:

http://www.batteriesnorthwest.com/ba...hool.cfm?TID=0

PS2 -- Do you have AGM sealed batteries?

Yes we have AGM sealed batteries. Voltage shows 12.3 while connected to 50 amp shore power. Appreciate your help with this.

[OTRA15]

In my lay opinion, a reading of 12.3 volts on shore power is not right, but uncle bob will know better, and maybe some experts will show up. Guessing that your converter/charger is not working right.

The dealer who checked this out may be one of the not-so-good ones IMO, so I would consider posting the dealer's name and asking for feedback. Also getting a second and third opinion, plus calling Airstream's 800 number hotline.

It would still be helpful to have you do the steps recommended earlier to unplug from shore power, wait an hour, then report the battery voltage with most 12-volt functions off. Your batteries may have also been compromised through all this. You could pull them out for testing at a battery shop, but if you are on the road, that is inconvenient to say the least.

Here are some recent battery threads for background reading:

http://www.airforums.com/forums/f540...es-170571.html
http://www.airforums.com/forums/f516...on-169925.html
http://www.airforums.com/forums/f449...lp-169693.html
http://www.airforums.com/forums/f317...ge-170153.html
http://www.airforums.com/forums/f449...or-170148.html
http://www.airforums.com/forums/f449...ud-165144.html

You also might want to scan the list of topics in the Batteries etc. sub-forum for more info:

http://www.airforums.com/forums/f449/

Good luck!

Peter

PS -- There is no need to Quote this post if your reply is next in line.

PS2 -- If you have to replace the converter/charger, you should get the best multi-stage one which won't over-charge and fry your batteries. Not sure what your OEM converter is.

[paiceman]

The converter sounds suspicious to me. When plugged into shore power, a good source and a trailer equipped with a factory converter one should normally see 13.6-13.7 on the panel. What this indicates is the batteries are charged, in fact over charged and the converter is charging them 24/7.

I replaced my factory converter with a four stage 50amp converter and we have had it in use as well as plugged into a 110v outlet while in storage for two months at this point. The new converter "hits" the batteries with an initial charge when we first plug into shore at 14.7, which normally quickly drops to 13.6 and then not too long after drops to 13.2 and as long as we are plugged into shore the converter keeps the batteries at 13.2 by virtue of a trickle charge OR if significant 12v usage is happening a charge will be used and then back to trickle - all in an effort to not overcharge or cook the batteries.

As noted earlier, I suspect the converter and I would (did) switch to a multi stage, as Airstream has done in the 2018 Classics, although ours is a different brand.

Bud

[uncle_bob]

Hi

One of these things is true:

1) The converter simply is not getting power from the 120V line

2) The converter output fuse(s) are blown and it's not putting anything out

3) The converter output voltage is low ( = it's broke, but not completely)

4) One or the other battery is faulty

5) The monitor panel is broken and it's lying to you

The most interesting one is number 5. Head over to Home Depot and grab a multimeter for $20 or so. Use it to measure the voltage at the battery terminals. See how that relates to what the monitor panel shows ....

Bob

[OTRA15]

Originally Posted by dbaur

Yes we have AGM sealed batteries. Voltage shows 12.3 while connected to 50 amp shore power. Appreciate your help with this.

Wondering if you have figured this out?

Thanks,

Peter

[dbaur]

Thanks for all the good advice and help. We have found that others with solar panels are experiencing the same problem and no solution at this point. Fortunately we are headed to Jackson Center on another issue and they have promised to check it out. Will update after our appointment in mid September.

[OTRA15]

Thanks for the update, and for identifying a possible shared problem. Good luck in JC.

Peter