Charging in Storage

[Quick Strike]

I just purchased a 2003 Greyhawk 28 RB. It is winterized and had been under a tarp in an outdoor storage facility. I want to keep the batteries charged in my pole barn where it will be kept for the rest of the winter. I looked in the manual and there was nothing on winter charging. I searched this topic here and want to make sure I am doing this right. I switched the main battery switch by the door off. I plugged the 110V cord in the water control compartment area into a wall outlet, and I put a battery tender on the chassis battery under the hood. Is that the correct way to do this?

Thanks - Steve in PA

[Mnwelsh]

It’s been a while since I researched this subject but a few years back I plugged my Seneca into 110 shore power when the RV was totally shut down. The house power switch inside the RV was off. I then checked the batteries on both the chassis and house side with my multimeter and they were both being charged. I could be wrong but I’m pretty sure that’s how it worked.

[Quick Strike]

OK Thanks. I will check with my multimeter to see what is going on.

[Grumpy]

2003 converter/charger will only charge house batteries, no provision to charge the chassis.

[che57vy]

When in storage I trickle charge the chassis battery with a well known brand charger that plugs in 120v outlet in rv other end goes into cigarette lighter plug. Of course I have RV plugged into shore power. Sometimes I have used a trickle charger on house battery.

[Rafstar]

I have a 2018 Seneca and I keep it plugged into 50 amp shore power when stored in a heated building with the main disconnect switch off. Am I doing the right thing or should I put all the batteries in a trickle charger?

Bob

[RVermont]

I just keep my unit plugged into 20 amp circuit and use the automatic charging systems on the unit. These keep every thing charged up. The newer units have battery isolation modules that “monitor “ the voltage in the different battery banks and open and close the charging cycle as needed.

Some people feel that using the supplied converter is not adequate or that they simply don’t trust the system and want to be sure so they use other types of chargers. Still others feel that the converter will fail if used constantly for years so they would rather shut the coach system off and use dedicated systems. All are good methods and just has to fit your needs.

I personally feel that I bought the unit and system to do what it is designed for so I use it, perhaps blindly but I understand the risks and feel they are worth taking.


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[RVermont]

I just noticed you said you had the 12 volt disconnect off. You might want to verify that that the converter will charge the batteries if the disconnect is off. I read somewhere that the switch had to be on and I leave mine on but really can not say one way or the other but you should check it out for your unit.


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[Wertles]

Once my house batteries are fully charged, I hit the battery disconnect button. I boiled my new battery last winter keeping it plugged in continuously. Apparently, the built in charger does not go into float mode. I also ran a battery tender to the constant 12V port on the dash and that keeps the chassis battery topped off. I plugged it inside the coach so I didn’t have to worry about leaving electronics outside. Once a month or so I would turn everything on for a day or two to make sure they were topped off then unplug and disconnect the house batteries until the next time.

[Rafstar]

Thanks for the information RVermont and Wertles. For what these batteries cost I want to make sure I get them to last as long as possible.

Bob

[RVermont]

Wertles gives a real life experience as to how he manages his and why.

Keep in mind that whatever you chose the battery disconnect does not fully shut off all power requirements. Batteries naturally lose charge and items like the propane detector can reduce voltage during storage. The four Seneca batteries have a fair amount of reserve but it is not endless so be sure to charge at a frequent basis and let them drop below 50%

I would venture to guess that the number one failure with batteries is pulling them below 50% charge.

Look at the converter that came with your unit to see if it has a float feature, my 2018 m2 has this so I am comfortable with using shore power however this is a personal perspective only.


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[Rafstar]

Good point RVermont!!!!!

I will look at the documentation this weekend and report back to the forum as to what I found out with regards to the 2018s on the S2RV chassis.

Thanks again for all the help.

Bob

[Quick Strike]

I went up last night after having the battery tender hooked to the chassis battery and shore power hooked up for most of the day. The tender was flashing green. This means the chassis battery is charged beyond the voltage required by the tender and the tender is not providing any charging. Solid green is charged but not overcharged. So, I think the shore power is charging both batteries above the voltage of the tender. I am headed up with the multimeter now. Maybe it is best to plug it into shore power for a few hours every week?

[WinnieView]

Originally Posted by Quick Strike

I went up last night after having the battery tender hooked to the chassis battery and shore power hooked up for most of the day. The tender was flashing green. This means the chassis battery is charged beyond the voltage required by the tender and the tender is not providing any charging. Solid green is charged but not overcharged. So, I think the shore power is charging both batteries above the voltage of the tender. I am headed up with the multimeter now. Maybe it is best to plug it into shore power for a few hours every week?

Yep. Put your multimeter on the chassis battery while on shore power and with the 12 volt disconnect for the coach On, and then turn it Off and check with the multimeter again.

We have installed on all our motorhomes a cheap device called a Trik-L-Start which takes the power from the coach battery charger and feeds it to the chassis battery while in storage.

Some motorhomes are wired from the factory to charge the chassis battery while on shore power, and some are wired so that the house battery is charged while the engine is running.

[Wertles]

Originally Posted by Quick Strike

I went up last night after having the battery tender hooked to the chassis battery and shore power hooked up for most of the day. The tender was flashing green. This means the chassis battery is charged beyond the voltage required by the tender and the tender is not providing any charging. Solid green is charged but not overcharged. So, I think the shore power is charging both batteries above the voltage of the tender. I am headed up with the multimeter now. Maybe it is best to plug it into shore power for a few hours every week?

If you have an actual brand Battery Tender, flashing green means the battery is between 80-100% charged and is still charging. Solid green means it’s 100% charged and in float mode. The two other brand tenders I have act the same way.

You can hook it up every week if you want. I do it once every 4-6 weeks and find the batteries to be in that 80-100% charged state when I do it.

Each MotorHome will be a little different in its charging setup. In my Class C, only the house batteries will be charged when plugged in to shore power, engine running or with the generator running. The chassis battery is on its own for charging. My class A will charge both in any scenario.

[Quick Strike]

I couldn't read the writing on the tender last night. Yes, flashing green is above 85% charged and green is float mode at fully charged. So, the house battery is charged by the land line, but not the chassis battery. I checked the house battery with the multimeter and it was a 13.6 volts with the shore line connected, but around 13 volts with the line disconnected. The chassis battery did not change when the landline was plugged into the barn. It was around 12.5 volts. So, I am back to the tender on the chassis battery to keep it charged and and the landline plugged in to charge the house battery.

[NH_camper]

The brand "Battery Tender" makes a very good line of battery maintainers that you can leave connected long term. Beware of cheaper products like the ones a well known tool store sells.