Solar confusion and frustration

[graygoose]

Hi all,
Last year we had 2/100 watt Go Power flex panels (GP-PWM 30), along with upgrading the converter and batteries from Airstream stock for our 2017 Airstream Serenity (28ft). We recently tested it, again, here in AZ with sunny skies and came to the same conclusion, it doesn’t seem to hold a charge for very long. One would think that after spending $2000, we would be able to go through the night and stay above 75% ?? We unplugged all small appliances etc, except the tv for 1 hr, fridge on propane, water heater off, used small lanterns, and then after an hour the battery % dropped from 100 to 72.... is that normal? We’d like to have the capability to boondock for a few days at least, and want to figure this out, do we maybe upgrade to lithium batteries ?(currently flooded), is it possibly the stock wiring isn’t sufficient ?(we purchased it wired for solar). We are on the fence about spending additional on solar, or just getting a generator.
Thanks~

[fran&frank]

You need to tell us what batteries you have for us to answer your question.--Frank

[xrvr]

Battery any good.?

[GMFL]

Hello,
I will send you a PM with my contact info. I will try to help you figure this out. There is more information needed, like brand and Size batteries you have and so forth. One problem you have is Flex panels. They do not last very long and are less than ideal.

[ROBERT CROSS]

That IS a lot of $$$ for a 200w flexible system.
I noticed that your controller, (GP-PWM 30) is not Lithium compatible. Maybe the best/first option is to bring up your concerns with the installer.

Bob
🇺🇸

[daleyocum]

The job of solar is to charge your batteries during the day. When you say you started at 100% and went down to 72%, was that at the start of the evening? If so that’s either a battery issue or something else in your trailer is drawing significant current.

Flooded batteries are notoriously easy to damage by draining them below 50%. Dealers are known for this on their sales lots. Our trailers will do this on their own in storage over a month as well because the Store/Use switch doesn’t completely disconnect everything. Many have installed separate battery disconnect switches for that reason. Until 2018, Airstream had a very primitive power converter/charger in the trailers that was known to not float batteries well. If your trailer was plugged in for extended periods of time that could have also killed your batteries.

It could well be your batteries will need to be replaced, preferably with AGM or lithium. If the later you’ll need to make sure your solar charge controller and power converter are lithium compatible.

[Troutboy]

two potential issues:
1. Bad batteries - can’t hold charge anymore. Have them tested especially if they are the original batteries that came with the AS.
2. If batteries are nit getting charged up fast enough and are in good condition, then you have other issues. Flex panels failing, or wiring circuit issues preventing power getting to charger and battery.

Sounds more like a battery issue, also, if you are running heater at night, you could easily drop batteries that much depending on temp. GMFL will help, give him a call

[Patandlinda]

Originally Posted by GMFL

Hello,
I will send you a PM with my contact info. I will try to help you figure this out. There is more information needed, like brand and Size batteries you have and so forth. One problem you have is Flex panels. They do not last very long and are less than ideal.

The best semi flex panels are Lensun . We have had them now for 2 years with a Victron controller . 2 6 Interstate batteries wired in series . This issue is foreign to us , just saying . We carry a 80 watt go power portable and have not had to use it . Sometimes a Honda Generator in case and have not had to use it . Pat

[Patandlinda]

Originally Posted by daleyocum

The job of solar is to charge your batteries during the day. When you say you started at 100% and went down to 72%, was that at the start of the evening? If so that’s either a battery issue or something else in your trailer is drawing significant current.

Flooded batteries are notoriously easy to damage by draining them below 50%. Dealers are known for this on their sales lots. Our trailers will do this on their own in storage over a month as well because the Store/Use switch doesn’t completely disconnect everything. Many have installed separate battery disconnect switches for that reason. Until 2018, Airstream had a very primitive power converter/charger in the trailers that was known to not float batteries well. If your trailer was plugged in for extended periods of time that could have also killed your batteries.

It could well be your batteries will need to be replaced, preferably with AGM or lithium. If the later you’ll need to make sure your solar charge controller and power converter are lithium compatible.

Agree except for our Interstates I just replaced after 6 years . Don’t I feel the need to spend all that cash on Lithum and agm . The 6 volts we have are wired in series . Charging which our solar does , good controller and checking water . Pat

[Patandlinda]

Originally Posted by ROBERT CROSS

That IS a lot of $$$ for a 200w flexible system.
I noticed that your controller, (GP-PWM 30) is not Lithium compatible. Maybe the best/first option is to bring up your concerns with the installer.

Bob
🇺🇸

Our system I installed was about 500 , 180 watts . The batteries , 2 Interstate , 6 volts were already installed . Bought Victron controller , Victron battery monitor , 3 60 watt panels and marine switches , wiring , tool and really not hard to do . Pat

[graygoose]

We have 2 Interstate 6v deep cycle extreme (GC2) batteries. We had them installed at an Airstream dealer which is why I’m sure it was more costly. Further research is telling us that if we get the lithium batteries we will most likely need to upgrade the controller and whatever else.

[Antique Pedaler]

When we had 2 100 watt system installed, the first thing the installer did was to replace the factory solar ready wiring with wire twice the capacity.

[GMFL]

Originally Posted by graygoose

We have 2 Interstate 6v deep cycle extreme (GC2) batteries. We had them installed at an Airstream dealer which is why I’m sure it was more costly. Further research is telling us that if we get the lithium batteries we will most likely need to upgrade the controller and whatever else.

That’s correct. You will need a converter/charger that will charge the Lithium batteries with a specific charge profile.

[new2trailer]

I second Dale Yocum’s evaluation. Your system is doing its job by getting your batteries to 100%. Your battery is not doing its job. My system is similar and it will charge battery to 100%. The battery will last overnight, even when I’m using my furnace overnight.

[Toasterlife]

It sounds like your batteries may be on their way out - Airstream is notorious for adding power hungry "vampire" gadgets that suck power even when turned off. Another thing is as the temperatures drop at night in AZ your power output will plunge regardess of draw. I am trying to figure out how to make a fleece "Battery cozy" much like a tea cozy to wrap up my batteries in the late afternoon to slow down the cooling process at night. In order to economize on battery power we use rechargeable lucy lights inside and use the water pump judiciously , take showers at mid day giving the solar time to recharge before sundown etc.

[AirMiles]

There's nothing wrong with using the factory prewire with 200W in parallel. Don't waste your money on upgrading the factory prewire. I run 600W of panels on the prewire with less than 3% voltage drop with some "fancy wiring".

There's nothing wrong with 6V golf cart batteries. I run two 6V in series and they easily power my daily power needs. With the solar plus the 6V golf cart batteries, I can watch TV all day, run both fantastic fans all day and night, run the propane furnace at 68 degrees all night when needed, and run all the lights and water pump as needed.

If your solar is charging the batteries and the batteries are good, you shouldn't be lacking on battery power.

Now with that out of the way, you have a problem because your solar and 6V batteries are not performing as well as suggested above. Maybe the 6V batteries you got were old and damaged before being installed in your Airstream. Yes even brand new batteries that have been sitting around for a year can be damaged beyond usefulness even though they are new. Also if they are connected to a non-solar Airstream for over a month they can also be damaged beyond usefulness. This happens on dealer lots all the time. I suspect your batteries are bad.

To test your batteries, buy a hydrometer: https://www.amazon.com/E-Z-Red-SP101...b-df5d6860e9af watch a video on Youtube on how to use it. It will tell you if your battery is damaged.

It would also help if you could share some voltage readings. To do this you need a voltage meter: https://www.amazon.com/Proster-Auto-...tomotive%2C172

These are the tools I would use to diagnose your problem. It could be the flexible solar panels. It could be the wire connections between the panels and the solar prewire. I could be the wire connections between the solar prewire and your solar controller. It could be your solar controller or it could be the wires between your solar controller and the battery (busbars). There's a lot of connections and parts that could be causing your problems.

I would start with buying the $11 hydrometer and testing the battery. I'd bet that your battery has been damaged beyond usefulness. With these tools, you will know what's wrong before spending money replacing parts that don't need replacing.

[AirMiles]

Here is a Battery Maintenance Sheet from Trojan for Wet Cell Golf Cart Batteries. It tells how to use a Hydrometer along with many other excellent maintenance tips. Have you kept the water levels up on your battery? Following the checklists on that Battery Maintenance sheet may help you resolve your problem.

https://www.trojanbattery.com/tech-s...y-maintenance/

[OTRA15]

Originally Posted by graygoose

We have 2 Interstate 6v deep cycle extreme (GC2) batteries. We had them installed at an Airstream dealer which is why I’m sure it was more costly. Further research is telling us that if we get the lithium batteries we will most likely need to upgrade the controller and whatever else.

Great advice from AirMiles in the last two posts. After you give new detailed feedback, folks will be able to provide more specific suggestions IMO.

Good luck,

Peter

[graygoose]

Thank you for all the information! It sounds like a little bit of a few things, so we will get it checked out by the installer.

[uncle_bob]

Hi

One thing not yet mentioned:

It sounds like you are reading battery charge level by looking at a voltage. The stock monitors in the AS work that way. This is not a great way to tell what's what. You can easily get a "100%" when the batteries are charged to 80%. Going from that 80% to 75% is not all that far .....

Getting lead acid batteries up to "full" is an all day process if you are hooked to shore power. Your monitor will read "full" long before things actually are full (like for the last 2/3 of the process ...). Doing the same thing on 200W solar this time of year might take weeks.

Bob