Battery/fridge question

[AlaskaJeff]

I am putting my 5th wheel in storage for about a week in Daytona Beach while I travel to South Florida to visit relatives. I would like to keep my fridge/freezer on while it is in storage, and I would also like to unhook the battery so there isn't any possibility of a draw. My plan is to get the fridge going on propane and then unhook the battery. Possible?

[chuckster57]

Nope. The controls for the fridge need 12V to operate.

[AlaskaJeff]

Originally Posted by chuckster57

Nope. The controls for the fridge need 12V to operate.

Ok, thanks. I live off grid in Alaska and use a propane fridge. I light it with a piezo lighter and it will run forever as long as there is gas. Is there much of a draw on the RV fridge with 12 volt while using it as I stated? Thanks.

[chuckster57]

Make/ model? If it’s a Norcold 2118 it won’t last overnight.

[AlaskaJeff]

Originally Posted by chuckster57

Make/ model? If it’s a Norcold 2118 it won’t last overnight.

Dometic DM2652LBX

[chuckster57]

Sorry I forgot to ask what size battery....been a long week.

[AlaskaJeff]

Interstate Deep Cycle 12v - 550CCA 690MCA

Thanks for your help.

[chuckster57]

Sounds like a group 24. I have my doubts it will last a week. You would have to pull the fuses for EVERYTHING else 12V that draws all the time. I’m sure there is a mathematical way to figure it out but I’m not THAT good at figuring all that out.

[sourdough]

Originally Posted by AlaskaJeff

I am putting my 5th wheel in storage for about a week in Daytona Beach while I travel to South Florida to visit relatives. I would like to keep my fridge/freezer on while it is in storage, and I would also like to unhook the battery so there isn't any possibility of a draw. My plan is to get the fridge going on propane and then unhook the battery. Possible?

I guess I'm wondering about "unhooking" the battery while you are gone for a week?? The fridge can run on propane but you need 12vdc to operate it. The need to disconnect the 12vdc for a 1 week trip???

[AlaskaJeff]

Originally Posted by chuckster57

Sounds like a group 24. I have my doubts it will last a week. You would have to pull the fuses for EVERYTHING else 12V that draws all the time. I’m sure there is a mathematical way to figure it out but I’m not THAT good at figuring all that out.

Yes, it is a group 24. Thanks for your help.

[AlaskaJeff]

Originally Posted by sourdough

I guess I'm wondering about "unhooking" the battery while you are gone for a week?? The fridge can run on propane but you need 12vdc to operate it. The need to disconnect the 12vdc for a 1 week trip???

Well, like I stated before, I live off grid in Alaska and my propane fridge runs without any sort of battery or power. I light it with a piezo lighter. I was wanting to see if I could run my RV fridge on gas only and save my battery from losing power.

[Rick]

Make sure to turn off the Climate Control.
https://www.manualslib.com/manual/78...page=15#manual

[flybouy]

Here's what's going on, the fridge you reference lighting sounds like it has a standing pilot light and is controlled with a simple thermocouple and not a thermistor. Your RV fridge has a 12vdc control board that operates the gas valve and the gas igniter. Some units have door perimeter heaters as well.

Your RV has several parasitic items that will drain your battery including propane detectors, radio (to maintain the radio's settings), TV antenna if left in the OTA or outside antenna setting.

Your battery is not a true deep cycle battery as they do not list CCA (cold cranking amps). Just guessing but I'd say your reserve capacity Amp Hour rating isn't much.

Bottom line, with a new battery maybe a couple days depending on temperatures outside. Certainly not weeks.

Now follows the comments from folks with solar arrays, batteries off of a WWII submarine, Mr. Fusion mods from a 1980's Delorean......

[JRTJH]

I think the question is: Can I run my Dometic 2652 refrigerator without a battery connected to it?

The answer is: No.

In years past, back when flint sparkers were the rule (before piezo-electric systems), RV refrigerators did not have any 12 VDC connections. They were constructed the same as the OP's propane refrigerator in his house. Everything was "mechanically controlled". There was a "bi-metal thermostat" that controlled the gas valve, a "standing pilot light" that always burned and a "thermocouple" that controlled the gas valve operation. That "strictly mechanical system" would operate without any electrical connection.

Today's Dometic refrigerators are not built and do not operate that way. They have a piezo-electric ignition system that is controlled by a thermistor input to an electrically controlled "gas management system" that relies on no standing pilot, no thermocouple and no mechanical "bi-metal thermostat". Today's "step into more accurate control" removed the capability to operate the refrigerator without a battery.

Can the refrigerator be modified "back to the old system" ? Yes, but in doing so, the entire current system would need to be removed and "if you can find the parts" a completely different cooling system would need to be installed. For most, it would be cheaper (much cheaper) to leave the trailer connected to shore power and leave the refrigerator operating as it does. The cost of paying for a campsite for a week is "peanuts" compared to the cost of modifying a "modern Dometic 2652" so it could operate without a battery. Heck, even buying 10 batteries so the system is "big enough to last a week" would "cost peanuts" when compared to the modification.

ADDED: I see Marshall was typing the same time as me. His post was at 1028, mine at 1029...

[Mainer]

Your battery fully charged, new held 81 AmpereHours. Your fridge's 12 volt fuse is 3 Amps, generally fuses are 110-150% of expected load. Assuming a draw of 2 Amps your battery COULD POSSIBLY last about 40 hours, IF all the safety equipment and entertainment system was completely shut off.

What you have as a battery is what is legally required to set your brakes if it fell off the TV on the road. You probably wouldn't last the night without needing AC.

Sorry for the bad news.

[LHaven]

Originally Posted by AlaskaJeff

I am putting my 5th wheel in storage for about a week in Daytona Beach while I travel to South Florida to visit relatives. I would like to keep my fridge/freezer on while it is in storage, and I would also like to unhook the battery so there isn't any possibility of a draw. My plan is to get the fridge going on propane and then unhook the battery. Possible?

Oh, man, I made that misassumption once, and paid dearly for it.

Prior to the rig we bought in 1999, my only experience with a propane fridge was in a 1970 Skamper, the old style pilot fridge that didn't need power. So I thought my new fridge worked on the same principle.

In 2004, our TV developed a transmission problem in NM that took the local one-horse dealer a week to fix. We left our new rig dry-parked in the campground with the fridge running, took a rental 400 miles home to handle an important business appointment, and drove it back to pick up the TV.

The battery was dead, and the contents were so foul not even the coyotes would eat them. It was a good thing God created turkey vultures. It took us more than a year of no camping to get the stink out of the fridge, as thawed meat juices had dripped through the seams in the freezer compartment. It was fortunate we lived in the desert, or they never would have dissipated.

[flybouy]

Originally Posted by LHaven

Oh, man, I made that misassumption once, and paid dearly for it.

Prior to the rig we bought in 1999, my only experience with a propane fridge was in a 1970 Skamper, the old style pilot fridge that didn't need power. So I thought my new fridge worked on the same principle.

In 2004, our TV developed a transmission problem in NM that took the local one-horse dealer a week to fix. We left our new rig dry-parked in the campground with the fridge running, took a rental 400 miles home to handle an important business appointment, and drove it back to pick up the TV.

The battery was dead, and the contents were so foul not even the coyotes would eat them. It was a good thing God created turkey vultures. It took us more than a year of no camping to get the stink out of the fridge, as thawed meat juices had dripped through the seams in the freezer compartment. It was fortunate we lived in the desert, or they never would have dissipated.

I think I'd have pulled out the fridge and torched it. During my tenure in the restaurant business I've looked at some abandoned spaces where rotting food was left behind in reach in and walk in refers. It's a smell you never forget!

[chuckster57]

Not much worse than a customer dropping off a unit and not cleaning out the fridge, not telling us anything was in it and a week or two later working on it. I’d almost rather work on a full black tank.

[LHaven]

Originally Posted by flybouy

I think I'd have pulled out the fridge and torched it. During my tenure in the restaurant business I've looked at some abandoned spaces where rotting food was left behind in reach in and walk in refers. It's a smell you never forget!

We tried multiple different remedies -- bleach, vinegar, commercial crystals, old newspapers, activated carbon powders... Some we left in place for months, while our rig was being stored.

I don't remember which one worked best, but in the end, it was impossible to tell anything had ever happened in the fridge. So it can be done.

[chuckster57]

Coffee grounds. Or so I’ve heard.