Replacement House Battery

[ASI]

Hi Everyone, I have read many, many, many posts on battery replacement along with inverter, etc, etc, etc, but it's so confusing I thought I would post this situation. I have a 2009 Interstate and the house battery is shot. We have only owned it for a couple of years, and it might have been bad when we bought it or I may have killed it with kindness. I normally keep it plugged in and we have used it several times with shore power and once with the generator running. I started the generator while it was still plugged into 30 amp electric. The unit has the original (assuming) Tripp-Lite DC to AC inverter/charger.

Here are my questions:
Should the switch be in the line charge only position when plugged in between trips?
Will leaving it plugged in continuously harm the house battery?
When plugged in does the battery voltage switch shows the charging voltage?
Do I need to unplug to read real voltage?
Considering I am still learning and don't really know what upgrades I need, is there a particular battery we should use as a cost effective replacement until we decide on upgrades? I believe I have seen threads recommending a Walmart or Sams Battery.
I am assuming I have a 12volt, but have also seen threads replacing with 2 six volts if they fit. Should I pursue that?

Any thing else that might make a difference or I need to consider?

[73shark]

I think your model has the stacked twin 12V Lifeline AGM batteries in the curbside rear corner under the lounge. I don't know if a twin setup. General consensus on the forum is Lifeline is at the top of the heap for long life albeit expensive but like everything in life, you get what you pay for.

You can search this section of the forum as there is a lot of discussion re: your question.

[UKDUDE]

What 73Shark says, and in addition, if you normally keep it plugged in, with the TrippLite that will destroy the batteries since it's not a smart charger.
If you're going to keep the Interstate, it's worth changing the TrippLite for a Magnum, which is what Airstream now uses in the Interstate.

[Boxster1971]

Originally Posted by ASI

Hi Everyone, I have read many, many, many posts on battery replacement along with inverter, etc, etc, etc, but it's so confusing I thought I would post this situation. I have a 2009 Interstate and the house battery is shot. ...

Here are my questions:
Should the switch be in the line charge only position when plugged in between trips?
ANS: The switch on the Tripp-Lite inverter/charger has three positions: "AUTO/REMOTE, CHARGE ONLY and DC OFF. I assume you are referring to the CHARGE ONLY position. That is OK for charging the batteries between trips. But note the cautions from 73shark and UKDUDE; you don't want to leave the charger plugged in as it does not have a proper float voltage load and will fry the batteries by overcharging. You can disable the charger function via the dip switches on the unit if you need to keep it plugged in for other reasons after the batteries are charged. I've attached a copy of the Tripp-Lite owners manual with more info if you don't have a copy.

Will leaving it plugged in continuously harm the house battery?
ANS: Yes!

When plugged in does the battery voltage switch shows the charging voltage?
ANS: Yes.

Do I need to unplug to read real voltage?
ANS: Yes - to get the true battery voltage you need to stop the charging.

Considering I am still learning and don't really know what upgrades I need, is there a particular battery we should use as a cost effective replacement until we decide on upgrades? I believe I have seen threads recommending a Walmart or Sams Battery.
ANS: Best to replace with Lifeline AGM batteries or other good quality maintenance free sealed batteries. You don't want to use regular wet cell batteries because they are in a stacked box and cant be serviced.

I am assuming I have a 12volt, but have also seen threads replacing with 2 six volts if they fit. Should I pursue that?
ANS: Yes - there are a pair of 12V batteries connected in parallel. You could replace with two 6V batteries connected in series to give 12V, but you have to be sure they will fit. I'm attaching an image of the battery box from the part manual.

Any thing else that might make a difference or I need to consider?
ANS: Consider replacing the Tripp-Lite with a Magnum MMS1012 1000 watt pure sine wave inverter/charger. But that can be a big DIY project unless you are really handy.

If you don't have the owners manual for your 2009 Interstate you can download a copy from Airstream at this link:
https://www.airstream.com/service/ma...ear_select=122

[ASI]

I should replace the batteries, plug them in to charge for a day, unplug the unit until ready to take a trip, then plug it in the day before to top off the batteries. Then when I get to a campground that has electricity, if I plug the unit in, how do I keep it from overcharging and damaging the batteries if I stay for a week?

[Boxster1971]

Originally Posted by ASI

I should replace the batteries, plug them in to charge for a day, unplug the unit until ready to take a trip, then plug it in the day before to top off the batteries. Then when I get to a campground that has electricity, if I plug the unit in, how do I keep it from overcharging and damaging the batteries if I stay for a week?

If you are using the 12V stuff like refrigerator, lights, propane etc. it's unlikely that you would be overcharging the batteries.

[73shark]

I forgot about the DIP switches (pg 5 & 6 in Mike's link, post 4). Don't know if this was why I got five years out of my batteries or not but here's the settings I used (which were different from the ones it came with): A1-UP, A2-DOWN, A3-DOWN, A4-UP, B1-UP, B2-UP, B3-UP, and B4-UP. Plus I left it on shore power when not on the road. YMMV.

If you are considering going w/ two 6V batteries in series, search the forum as someone here described in detail w/ pics how he did it.