Adding additional batteries - how much additional fridge time?

[NewToRVinNJ]

Hi there. I posted late last year about us camping at a state park and that they had very limited generator hours. Some of the feedback we got suggested we add batteries. Our main concern was the residential fridge was not able to stay running all night and the temperature was warmer than it should be.

Our motor home is at the dealership for warranty repairs so I’d like to get it done this week while it’s there. I asked them about it and they said adding 2 batteries would give us around an additional 5 hours of run time on the refrigerator. Does this sound right? I know it depends on brand but wanted to see if this was in the ballpark. I was hoping we would get more time because I think the inverter was beeping around 1 or 2 am so 5 extra hours wouldn’t be quite enough.

Thanks!

[Scottybdivin]

What RF do you have and how many and what type of batteries? For example, the Samsung RF 18 avarages about 10 Ah's. Two 6V batteries give you about 110-115 usable Ah to stay above 50%.

[twinboat]

If it came equipped with small batteries to start with and they are adding 2 more, that may be the case.

How many and what Group ( GP24, GP27, GP31, GP GC2 ) size do you have now.

Knowing the brand of fridge and if it has an ice maker will help too.

In any case, if not plugged in, its best to leave the ice maker off.

My apartment size 7.8 cf fridge avereges 3 AH. A GP24 battery may have 85 AHs in it and you can use about half. My fridge would run around 12 hours on one battery.

[nothermark]

5 hours sounds pretty short unless they meant 5 hours each or another 10 hours of run time.

When they started putting residentials in anything smaller than a DP users quickly found out that they needed two batteries installed, not the one common at the time. The Ford chassis is set up for two, usually under the step. That got from after dinner to morning and usually starting the generator. Sufficient for most folks who follow the pattern of starting the generator when they get out of bed so they can power up the water heater and make breakfast.

Given that I would expect you can get further into the day so solar could kick in but you are not going to get two nights in a row without generator time. You can do that with two batteries and no quiet hour hassle. Four batteries might solve your problem if you have a real hassle with NJ quiet hours. I'm not sure what they require. Come up to NY, I have not noticed any limits. ;-)

[Smitty77]

Another consideration is the mixing of new batteries with old batteries, usually not a good idea.

Answer some of the questions above, and then read what responses you get. I'd personally, listen to some of the battery related experts here on this forum!

Perhaps consider removing your at least 1 year old batteries, and selling them on Craigslists to recoup some costs. Then get matching new batteries, based upon the feed back from this gang...

Just tossing batteries at this, may not be cost effective in the long run... Doing so with a plan to get where you want to be, is more cost effective in the long run.

Best to you,
Smitty

[vsheetz]

Our coach comes with four 6v batteries. The RR option includes two additional for a total of six. We run through the night ok.

The fan in your propane furnace is the biggest consumer of electricity and it runs the most through the night if course.

[dons2346]

It is not the number of batteries, it is the total amp hours of those batteries.

Just for info, our Samsung 197 has gone over 20 hours without power with zero ill effects. Everything in the freezer was still frozen and the refer portion never got to 40. You just can't stand there, open the door and "surf" for your dinner.

If you can't go overnight, make sure your ice maker is turned off as it uses a lot of energy

[NewToRVinNJ]

Originally Posted by Scottybdivin

What RF do you have and how many and what type of batteries? For example, the Samsung RF 18 avarages about 10 Ah's. Two 6V batteries give you about 110-115 usable Ah to stay above 50%.

I honestly don’t know what kind of fridge I have. We have a 2017 Thor hurricane 34j. It has an ice maker.

[NewToRVinNJ]

Originally Posted by twinboat

If it came equipped with small batteries to start with and they are adding 2 more, that may be the case.

How many and what Group ( GP24, GP27, GP31, GP GC2 ) size do you have now.

Knowing the brand of fridge and if it has an ice maker will help too.

In any case, if not plugged in, its best to leave the ice maker off.

My apartment size 7.8 cf fridge avereges 3 AH. A GP24 battery may have 85 AHs in it and you can use about half. My fridge would run around 12 hours on one battery.

I don’t know what group size I have now or the brand of fridge. It does have an ice maker. It is an 11 cf fridge. That much I know.

[NewToRVinNJ]

Originally Posted by nothermark

5 hours sounds pretty short unless they meant 5 hours each or another 10 hours of run time.

When they started putting residentials in anything smaller than a DP users quickly found out that they needed two batteries installed, not the one common at the time. The Ford chassis is set up for two, usually under the step. That got from after dinner to morning and usually starting the generator. Sufficient for most folks who follow the pattern of starting the generator when they get out of bed so they can power up the water heater and make breakfast.

Given that I would expect you can get further into the day so solar could kick in but you are not going to get two nights in a row without generator time. You can do that with two batteries and no quiet hour hassle. Four batteries might solve your problem if you have a real hassle with NJ quiet hours. I'm not sure what they require. Come up to NY, I have not noticed any limits. ;-)

We ran the generator around an hour and half in the am and around 2.5 to 3 hours in the evening shutting it off at 9pm. We had the ice maker turned off. We actually were in a NY state park in Montauk! That’s the only place we’ve stayed with limits on generator.

[NewToRVinNJ]

Originally Posted by dons2346

It is not the number of batteries, it is the total amp hours of those batteries.

Just for info, our Samsung 197 has gone over 20 hours without power with zero ill effects. Everything in the freezer was still frozen and the refer portion never got to 40. You just can't stand there, open the door and "surf" for your dinner.

If you can't go overnight, make sure your ice maker is turned off as it uses a lot of energy

I guess I will ask the dealership what type of batteries they would be putting in. We definitely don’t keep fridge door open and we kept the ice maker turned off.

[twinboat]

You have to wonder if they let the batteries sit dead, while on the lot, before you bought it.

Dealers tend to do that. Maybe have them test them while you watch.

Hither Hills, in Montauk ? We love ocean front camping.

[pauldub]

You need to be sure that you have a decent converter or you won't get enough charge into the batteries by running the generator. If the converter can't charge the batteries adequately, more batteries won't help. What brand and model is your converter?

[NewToRVinNJ]

Originally Posted by twinboat

You have to wonder if they let the batteries sit dead, while on the lot, before you bought it.

Dealers tend to do that. Maybe have them test them while you watch.

Hither Hills, in Montauk ? We love ocean front camping.

We ordered our rv so it wasn’t sitting on the lot.

Yep hither hills! We loved it. My husband used to go with his family when he was a kid.