Thread Tools Search this Thread Display Modes
Old 02-18-2014, 02:51 PM   #1
4 Rivet Member
Cannonball's Avatar
2014 22' FB Sport
San Antonio , Texas
Join Date: Jan 2014
Posts: 483
Images: 1
Battery Switch Inside "On" or "Off"?

Ok, I have read the manual front to back, and am still confused. Our rig is a 2014 Sport 22FB. By the front bed is the battery disconnect switch. When the trailer is in storage, I turn that switch "off" to prevent any phantom drains. When we take the Airstream out, I turn the switch "on", and leave it on for the duration of the trip. We are not boondocking, but are connected to shore power while camping. Two questions:

1) Can the battery be overcharged by being connected to shore power with the battery switch in the "on " position for several days? What if I am connected to shore power, and leave the 7 pin plugged into the TV?

2) Under what circumstances, if any, would I want/need to turn the battery switch "off" while connected to shore power?

Thanks in advance.

Cannonball is offline   Reply With Quote
Old 02-18-2014, 03:38 PM   #2
DKB_SATX's Avatar

2017 26' Flying Cloud
1976 Argosy 28
Alamo Heights , Texas
Join Date: Aug 2006
Posts: 6,127
Images: 1
Blog Entries: 7
With the converter that Airstream supplies, you'll eventually overcharge the battery if you leave it on shore power all the time. If it's just on shore power when you're actually traveling and camping in it, that'll take a long time but it will likely shorten the life of your battery somewhat.

Whether the converter backfeeds your TV through the umbilical depends on your TV. Some have a diode that prevents it, some disconnect the charge line when the ignition is switched off, some would allow it. You're not likely to get enough current feeding back to harm your TV's battery even over weeks of having it plugged in, and any way the only time you're likely to be both on shore power and plugged into the TV is on an overnight stop where you don't unhitch.

I can't remember if the new ones isolate the battery from being charged in "store." I think they do, and in any event it would be easy to check. The tricky thing about the store/use solenoid is that the light is always on when you're plugged in, so you need to unplug to be 100% sure of the state of the solenoid. Unplug, switch to "store", check the battery voltage (at the battery posts directly), plug in, recheck the voltage. If it's the same (12.7-ish volts) then they're isolated when in Store, if the voltage jumps up then they're being charged in Store.

So, if they're isolated, you could switch to Store after a few days at a campsite when you're sure the batteries are fully charged. I think the propane detector is wired right to the batteries, so it'll eventually drain them and you'll need to charge again.

Someone with a trailer new enough to have that store/use switch will be along presently to give a more definitive answer. If I want to disconnect my battery I have to open the battery box, old-school like.


Zero Gravitas 2017 Flying Cloud 26U | Il Progetto 1976 Argosy 28 Center Bath | WBCCI# 15566

He has all of the virtues I dislike and none of the vices I admire. Sir Winston Churchill
DKB_SATX is online now   Reply With Quote
Old 02-18-2014, 03:53 PM   #3
Rivet Master
TBRich's Avatar

2006 19' Safari SE
Tucson , Arizona
Join Date: Jun 2007
Posts: 4,436
Images: 64
You are correct to switch to "store" while your rig is in storage and disconnected from shore power, for exactly the reasons you describe ... to isolate the battery from phantom draws. For long, extended times of storage some folks physically disconnect the batteries and put them on a battery minder to maintain them over the long haul, but for intermittent periods of storage you should be fine.

Likewise, you are correct in switching to "use" while camping in your rig...even if you are plugged into shore power. (In fact, if I am not mistaken, being plugged in overrides the disconnect ... at last that is the case with ours.) It is highly unlikely that your batteries will be overcharged when plugged in while you are camping in it because there are draws on the battery all the whole time ... lights, frig, propane detector, furnace, etc.

We store our rig at home, plugged into 30-amp continuously. We do not switch to "store" during that time, however we leave the frig on, use the lights, water pump, furnace, AC, TV and radio from time to time — we pretty much doing everything one would do while camping, but sleeping in it — so in our case, there are constant draws during our version of "storage" ... so far our batteries have, therefore, never overcharge.

We typically disconnect from the tow vehicle when we stop, even if we are just there for the night ... just to make sure.
TB & Greg and Abbey Schnauzer
AirForums #21900 . Membership Chair, 4C
Unit #3954
Travel Log: AZBambi...On the Road Again
TBRich is offline   Reply With Quote
Old 02-18-2014, 06:30 PM   #4
Rivet Master
1974 Argosy 20
2014 20' Flying Cloud
Kooskia , Idaho
Join Date: Jul 2009
Posts: 4,591
On my 2014 FC 20' when in the store mode, the battery is disconnected from the loads in the trailer except:

1.The propane detector which is always on and takes 6 to 8 mA constantly. It is not shut down by the Store/Use switch.
2.The optional inverter which is wired directly to the batteries and does not go through the Store disconnect. So, you could turn the inverter on by accident and run the batteries down even in the Store mode. My inverter has a large standby current of 1.75 amps, when doing nothing at all so that discharge is a potential for killing the batteries easily.

When in Store mode the converter/charger is disconnected from the batteries but will supply 12 volts for the lights and other 12 volt items in the rig. But it will not charge the batteries, or allow them to be discharged, other than the two items mentioned above.

I have a modern 3 stage converter/charger in my rig now, not the original Paralax which came with it from the factory. So, I have no problems leaving my Store switch on all the time. With the original Paralax I would probably limit the time that the rig was plugged in and the store switch on to maybe a week if the unit is unused. That would minimize the possibility of a battery overcharge situation. But it is not something you need to be paranoid about. Just don't leave the rig plugged in for months with the original Paralax converter/charger.

In looking at the 12 volt electrical diagram, it appears that the Tow Vehicle charge line is directly connected to the Airstream batteries and is not disconnected by the Store mode switch. So, if the Tow Vehicle is left plugged into the Airstream and does not have a relay in the tow vehicle itself, it will be charged by the converter/charger if the Store mode switch is left in the Use position, but not if it is in the Store position, same as the Airstream batteries. Some tow vehicles have an isolation relay, some do not. My 2012 Jeep Grand Cherokee does not. I believe Ford's do. No idea about GM vehicles.

The Use/Store switch is a relatively complicated thing to wrap your mind around, so don't stress if you don't understand it at first. It may take a while, I know it did with me and I am pretty electrically savy.
idroba is offline   Reply With Quote
Old 02-18-2014, 09:31 PM   #5
Rivet Master
2012 25' Flying Cloud
Battle Lake , Minnesota
Join Date: Jun 2009
Posts: 7,509
When stored we select "STORE" to isolate everything but the propane detector from the batteries.

When plugged into shore power we select "STORE" to isolate the batteries from being repeatedly overcharged and ruined by the Parallax converter.

We have a solar system to keep the batteries up.

The only time we select the "USE" position is when towing to keep the refrigerator running on propane, and when dry camping to power the 12 volt equipment.
dkottum is offline   Reply With Quote
Old 02-19-2014, 03:51 AM   #6
Rivet Master
r carl's Avatar
Vintage Kin Owner
Lin , Ne
Join Date: Dec 2009
Posts: 2,039
Originally Posted by dkottum View Post

When plugged into shore power we select "STORE" to isolate the batteries from being repeatedly overcharged and ruined by the Parallax converter.

Why doesn't your trailers electronics automatically charge your batteries?
The higher your expectations the fewer your options.
r carl is offline   Reply With Quote
Old 02-19-2014, 05:38 AM   #7
Rivet Master
Skater's Avatar
1995 30' Excella
Bowie , Maryland
Join Date: Apr 2005
Posts: 2,343
Originally Posted by r carl View Post
Why doesn't your trailers electronics automatically charge your batteries?
They do, but Airstream uses cheap single stage chargers and they overcharge the batteries.

We've replaced ours with a three stage charger, and now I never turn the switch to store.
1995 Airstream Classic 30' Excella 1000
2014 Ram 2500 Crew Cab with Cummins 6.7L Diesel

Sold but not forgotten: 1991 Airstream B190
Sold: 2006 F-250 6.0L Powerstroke Supercab
Skater is offline   Reply With Quote
Old 02-19-2014, 06:11 AM   #8
Rivet Master
r carl's Avatar
Vintage Kin Owner
Lin , Ne
Join Date: Dec 2009
Posts: 2,039
Originally Posted by Skater View Post
They do, but Airstream uses cheap single stage chargers and they overcharge the batteries.

We've replaced ours with a three stage charger, and now I never turn the switch to store.
Don't the single stage chargers have voltage regulators? My 1985 Avion with original electrics doesn't overcharge my batteries.
The higher your expectations the fewer your options.
r carl is offline   Reply With Quote
Old 02-20-2014, 07:50 AM   #9
Rivet Master
2012 25' Flying Cloud
Battle Lake , Minnesota
Join Date: Jun 2009
Posts: 7,509
There are many accounts of the stock Airstream converter overcharging and ruining batteries, other than that it works fine. (It ruined the batteries in two years on our 2007 Airstream before we bought this new trailer with the solar system.)

So by using the "STORE" battery position whenever plugged into external power, we never allow the converter to charge our batteries. Only the solar system does, or the truck when towing.
dkottum is offline   Reply With Quote
Old 07-05-2016, 09:29 AM   #10
4 Rivet Member
2015 23' Flying Cloud
Livermore , California
Join Date: Oct 2015
Posts: 367
I dug this thread up to figure out my store/use switch on our 2015 FC23D.

Right not we have the AS in our storage location plugged into 110. I have the multistage Intel-Power 4600 Converter/Charger.

The red light is constantly on but you can here the relay if you push use or store. I have been pushing store when we leave for the day.

What position should we leave the switch in while connected to 110?
cactusjk is offline   Reply With Quote
Old 07-31-2016, 02:25 PM   #11
1 Rivet Member
Patti G.'s Avatar
2015 25' FB Flying Cloud
Alexandria , Virginia
Join Date: Jul 2013
Posts: 8
Fellow Streamers....following and searching threads closely on the battery/converter/disconnect switch issue. I have a 25ft. FC 2015. Both batteries were replaced today, only 18 months old and I'm a maintenance junky. Try to do everything right. Latest situation and experiments with a followup question. I have been hooked up to shore power for the most part since mid-June. As you guys have suggested, I occasionally leave it in the store position...more often than not while on SP. One battery had been sucking up water. Just had it checked at Advance Auto and it is fried. I had been checking the water every couple of days..

Prior to testing the battery, I had noticed last night that the converter fan never turned off. This morning, I turned off SP, and used the inverter for the TV to test how long it would take to drain the batteries. They went from 12.7 volts to 10.5 in roughly 2 hours. Which led to testing the one battery that had been sucking up water. My guess is the converter never shut down because the fried battery would not accept a charge. I plan on upgrading my converter when I get home from this trip.

Now, here is what I don't get. With both batteries removed and on SP, the so called 12 volt appliances (fridge) were working. Lights worked. Only the LP monitor did not. Question: Is the converter still charging the fridge and the lights? Again, I had removed both batteries waiting to install the new ones. This leads me to the conclusion that while on SP, you really don't need the batteries at all with the exception of LP monitor?

I do understand the disconnect switch function. The other oddity was that with the batteries removed, and again, on SP, the Sea Level Monitor still showed the "battery" at 13.7 volts even thought I had removed the batteries?! (Switch was in "store") I know I'm jumping around with several issues, but they seem connected. Any help appreciated.

Patti G. is offline   Reply With Quote
Old 07-31-2016, 03:03 PM   #12
Rivet Master

2007 22' International CCD
Corona , California
Join Date: Jul 2013
Posts: 2,482
Battery Switch Inside "On" or "Off"?

Propane detector is wired to the battery side of the disconnect relay. With an open store/use relay and dead or disconnected batteries the propane detector would get no power from the convertor.

It's the way AS wired it....and the subject of some controversy.

Sent from my pocket Internet using Airstream Forums
'The Silver HamShack' (2007 International 22FB CCD 75th Aniversary model)
Multiple Yaesu Ham Radios inside and many antennae sprouting from roof, ProPride hitch
2012 shortbed crewcab 4x4 Toyota Taco TV with more antennae on it
rmkrum is offline   Reply With Quote
Old 07-31-2016, 03:03 PM   #13
Rivet Master
PKI's Avatar
2015 23' FB Flying Cloud
Walnut Creek , California
Join Date: May 2015
Posts: 1,562
Oh, what fun to learn how the systems on out coaches work.

First.....make sure the water in the battery bank is full. Only takes a minute to check and distilled water (not drinking water) is inexpensive. can.....not get all the parasitic loads disconnected.....well you can, but it's a fuse here and a cable there and well - install a disconnect on the main coach feed from the battery and include an in-line fuse. Look at Lewster's posts. He provided a suggestion and explained the need for a fuse. a general practice you won't kill the batteries, if you do not switch to store when on shore power at an overnight stop. See step first above. a general rule, you will kill the batteries if you store the trailer on shore power. The batteries need to be charged with a source that monitors their condition and only provides power when the charge drops. Too much charge, too little charge or no charge is a problem. The standard AS converter is single stage and charges at too high a rate.

Fifth......the parasitic draw will kill a battery bank in two to four weeks. Do not assume that because the trailer is in storage it will be OK. Driving the voltage of a wet cell battery below 12-12.2Vs is not helpful to battery life. not get all bent. A new battery bank is +/-$200 for a Walmart solution or you can fight with Interstate for replacements. However, it is not the end of the world if your batteries get killed. It is going to be an inconvenience and a bit of care is a good idea.

Seventh.....There are a lot of folks who know everything about the electrical system of an Airstream. They are the source of the above info. I just stole it from reading their posts. You can too.

PS - yes, the converter provides the trailer with 12 volts when on shore power with the battery bank removed. Do not believe the tongue jack would have power and it does the converter no good to not have the bank in the circuit. Edit - see post above on the LPG detector as well.

Good luck with the coach. Travel safe. Pat
PKI is offline   Reply With Quote
Old 12-07-2016, 03:38 PM   #14
3 Rivet Member
2017 27' International
Canfield , Ohio
Join Date: Jul 2015
Posts: 159
Well, I learned my lesson. I had my rig plugged in for 3 months and completely fried one battery. It was down a quart!.

Interstate didn't care. Replaced the 4-month-old battery and said Merry Christmas. The other battery has tested fine.

What three stage converter / charger would you recommend for a 2017 AS?

2017 Airstream International Signature 27FB Twin
turk123 is offline   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Land Yacht battery control center speedy45 Electrical - Systems, Generators, Batteries & Solar 2 11-19-2011 11:12 AM
Battery Tender and Univolt? AldeanFan Batteries, Univolts, Converters & Inverters 8 08-31-2011 11:16 AM
BATTERY ON/OFF SWITCH - What Do I Do? Fly at Night Batteries, Univolts, Converters & Inverters 36 08-30-2011 08:24 PM
Battery Bank Upgrade Gwuk Batteries, Univolts, Converters & Inverters 5 03-24-2011 08:18 AM
Only one battery charging heslinhotel Batteries, Univolts, Converters & Inverters 11 02-21-2011 08:49 PM

Virginia Campgrounds

Reviews provided by

Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities

Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 02:55 PM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.