Battery Isolator

[Bernie]

I am putting some thought in to adding a 12VDC fridge. I could mount a deep cycle in the bed, and a fridge in the back seat.

Correct me if I am wrong, but our stock batteries are dealt with like one battery by the charging system. If that is true, I would need a dual battery isolator (the stock batteries as my main, the deep cycle as my accessory battery). They way the fridge can run when the truck is off, and not drain the main batteries.

Has anyone done this before? Which isolator should I use? Do I need a sense wire?

As an alternative, is there a way to isolate one of my stock batteries? Is that a bad idea?

 

[MVenditti]

They use those type switches a lot on boats and such. Not sure how to wire with these trucks but a good idea. 2 batteries for truck and 2 for acc. Can switch to jump start yourself when needed but banks kept separate.

 

[Lordsman]

That requires a lot of juice. If you must go with battery power consider a solar panel to charge it while driving. A RV fridge(amonia) running off of a propane pilot works real well also. Just a thought from a former RVer

 

[Bernie]

I'm not talking a pilot light type, I am looking at something more like this:

Amazon.com: 43 Qt Portable Compact Refrigerator Freezer - EdgeStar: Kitchen & Dining

 

[Bill Stockard]

I'm not familar with the brand fridge-freezer you are looking at, but the 40 qt capacity Engel brand draws from 0. 7 to 2. 5 amps and will run a long time on the batteries if it is plugged in and the contents cooled down before plugging into the vehicle battery. I don't know how long you intend to run the cooler without running your engine, but it will stay cold for a quite long time without running on the battery, especially if it is packed full. The amp draw depends on the type and efficiency of compressor the fridge-freezer uses.



Bill

 

[Motorhead]

I hooked up a 75 amp Bosch constant duty relay for my friends fiver so he didn't have to unplug his trailer if he stopped for an over nighter. The relay is ignition activated. When the key is on it charges. when off, it is disconnected from the truck batteries and charging system.

 

[Allnew2Me]

I use an Engel fridge and it will run for several days on the two stock batteries with no problems. The Edgestar uses a little more current than the Engel, which uses a patented swing motor. The Edgestar uses a Danfoss compressor which is very efficient also.

If you use an isolator, a solenoid-type would be better than the diode versions, which will suffer a voltage drop. Even better is a VSR which will only charge the aux batteries after the primary batteries are up and going. One example is below.



Amazon.com: BEP VOLTAGE SENSITIVE RELAY 710-125A (Image for Reference): Sports & Outdoors





If you go with the third battery it should be the same type as the starting batteries, which should also be a matched pair to allow better charge performance. Make sure you have a correctly-sized wire back to the battery in the bed or it won't recharge properly.

 

[AH64ID]

After having several very expensive isolators fail over the years we have changed how we operate. The simplest and easiest setup is an oil psi switch and a heavy-duty continuous-duty solenoid. You make the oil psi switch close the solenoid, so you only have the aux batteries tied to the mains when the engine is running. Just get a solenoid that can run the rated current of the alternator for 30 minutes and you will be good to go.

I do suggest using a start/deep cycle battery so the charge rate is the same on all 4. It's more money but you would be in the best shape by having 3 or 4 Sears Platinum's.

Cole Hersee Co. 24143 12V CONTINUOUS DUTY SOLENOID 200A | Fisheries Supply

Amazon.com: OIL PRESSURE SWITCH 6 PSI: Sports & Outdoors

 

[DFrank]

I need to add an isolator to keep my truck camper from draining the main batteries.

I have two deep cells stashed in front of the wheel well.

I did a split kit that added a new seven pin outlet in the same area.

The house batteries get charged via the hot off this new trailer plug, which also allows the camper to drain the truck batteries when parked.

I have a solenoid ready to install, but I'm not sure if I should somehow tie it to the trailer wire, or just eliminate that wire at the camper's plug and run a fatter wire straight from the isolator to the in bed batteries.

I was surprised to kill the truck batteries with just 2 nights of lights and forced air heat, in single degree temps. I've done this before with no issues. Fortunately a jump start was not hard to come by in the ski lot, but it was so drained that it struggled even to jump.

There was a lot of phone charging and camera battery charging. I wouldn't have expected those to drain much, would they?

Thanks,

Dave

 

[DFrank]

I need to add an isolator to keep my truck camper from draining the main batteries.

I have two deep cells stashed in front of the wheel well. (second one just added after this issue)

I did a split kit that added a new seven pin outlet in the same area.

The house batteries get charged via the hot off this new trailer plug, which also allows the camper to drain the truck batteries when parked.

I have a solenoid ready to install, but I'm not sure if I should somehow tie it to the trailer wire, or just eliminate that wire at the camper's plug and run a fatter wire straight from the isolator to the in bed batteries.

I was surprised to kill the truck batteries with just 2 nights of lights and forced air heat, in single degree temps. I've done this before with no issues. Fortunately a jump start was not hard to come by in the ski lot, but it was so drained that it struggled even to jump.

There was a lot of phone charging and camera battery charging. I wouldn't have expected those to drain much, would they?

Thanks,

Dave

 

[Bob4x4]

I'm not familar with the brand fridge-freezer you are looking at, but the 40 qt capacity Engel brand draws from 0. 7 to 2. 5 amps and will run a long time on the batteries if it is plugged in and the contents cooled down before plugging into the vehicle battery. I don't know how long you intend to run the cooler without running your engine, but it will stay cold for a quite long time without running on the battery, especially if it is packed full. The amp draw depends on the type and efficiency of compressor the fridge-freezer uses.

Bill

I don't think all the new portable reefers use compressors ??

 

[Bob4x4]

I need to add an isolator to keep my truck camper from draining the main batteries.

I have two deep cells stashed in front of the wheel well. (second one just added after this issue)

I did a split kit that added a new seven pin outlet in the same area.

The house batteries get charged via the hot off this new trailer plug, which also allows the camper to drain the truck batteries when parked.

I have a solenoid ready to install, but I'm not sure if I should somehow tie it to the trailer wire, or just eliminate that wire at the camper's plug and run a fatter wire straight from the isolator to the in bed batteries.

I was surprised to kill the truck batteries with just 2 nights of lights and forced air heat, in single degree temps. I've done this before with no issues. Fortunately a jump start was not hard to come by in the ski lot, but it was so drained that it struggled even to jump.

There was a lot of phone charging and camera battery charging. I wouldn't have expected those to drain much, would they?

Thanks,

Dave

The furnace fans use many watts,that is the biggest issue when boondocking in the winter. That's why the little propane cat heaters have become so popular.
One of the reasons I have solar on my airsteam

 

[DFrank]

Sorry for the double post.

on those newer cat heaters, like the Buddy heatwave III, are people running them unvented overnight?

I know they burn clean enough, but do they use up all the O2? Which model do people recommend?

Another issue we have with heat, is the CAbover getting much hotter than the dinette, where the kid sleeps. He wants it turned up, while I want it set to 50 degrees. Will a small fan fix that? We are in a ten foot pop up truck camper.

 

[Bob4x4]

Just crack the vent above the overhead it will fix both items

 

[mwilson]

Just crack the vent above the overhead it will fix both items

No way would I run an unvented oxygen eating carbon monoxide producing heater with people sleeping.



Have seen entire families wiped out in drafty hunting camps doing that very thing.



If someone woke up in the night and in a semi comatose state closed the roof vent you might well be done for.



If you insist on doing so install a quality carbon monoxide detector. Please... .



Wife just said that if you not happy that the world did not end as the Mayans predicted then by all means proceed... ... .



We both have lived in Maine with it's severely cold winters all of our lives and have witnessed many senseless deaths from people simply trying to stay warm overnight with unvented propane heaters.



Off the soapbox now.





Mike.

 

[Bob4x4]

No way would I run an unvented oxygen eating carbon monoxide producing heater with people sleeping.

Have seen entire families wiped out in drafty hunting camps doing that very thing.

If someone woke up in the night and in a semi comatose state closed the roof vent you might well be done for.

If you insist on doing so install a quality carbon monoxide detector. Please... .

Mike.

Check out the rv forums

http://www.buy.com/prod/rv-portable...off-system/230614101.html?listingId=247615053

 

[mwilson]

Check out the rv forums



http://www.buy.com/prod/rv-portable...off-system/230614101.html?listingId=247615053

Understood, but I still would not trust it. Just could not do it.



Family has several of the Buddy heaters, main use is in ice shacks. Wind whistles through those pretty strong, plenty fresh air but we don't stay in the shacks overnight.



I was almost taken out while welding in a shop by carbon monoxide, now have no tolerance for it all. I can sense it immediately.



Not worth the risk to myself or the loved ones.



Mike.