Powering a fridge in a diesel truck

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Salty4Life

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I’m wanting to run a fridge in my truck all the time. It’s a 2018 ram 2500 6.7 Cummins. The truck comes from the factory with two batteries and a 220 amp alternator. With that in mind, would solar panels be necessary to insure the truck starts every morning? About how long would the truck have to run to top off the batteries after running a fridge all night?
 

systemdelete

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Depends on what model fridge, what temp you have it set at, and the ambient temp where it is during operation.


For my 50qt ARB set at 38f, in the back of my FJ an 80w panel mounted on the hood with a quality mppt solar charger put in enough amps that the truck always started. Looking back at the logs, I would have been slightly better off(for LONG term battery life) with around 100w worth of the same panel. In my new setup I’m using two 55w panels for a total of 110w of potential input to correct for that. Though I have a larger mounting surface in the new rig so it was easier to optimize.
 

Salty4Life

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I’m looking at a 53 quart Alpicool. It’s either that or a bigger yeti cooler to live in my truck. Buying ice every other day is getting old. That fridge is comparable in price to a yeti but if I need to get solar panels, mounts and a solar charger, the cost would obviously go way up as would the complexity.
 

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if you are planning on running a fridge 24/7 365 i would go ahead and pay the extra and get the solar, charge controller and a dedicated battery or two. You dont want to be stranded because a fridge and other electronics sucked all the juice from your starter batteries.
If you plan on just using the fridge while driving and overnight youll likely be fine with what you have unless your batteries are going bad.
 
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Docrandy

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I’m looking at a 53 quart Alpicool. It’s either that or a bigger yeti cooler to live in my truck. Buying ice every other day is getting old. That fridge is comparable in price to a yeti but if I need to get solar panels, mounts and a solar charger, the cost would obviously go way up as would the complexity.
I am looking at the same one I am planning on doing a full solar setup on my rig that will probably be overkill for anything I will ever need but with the price of solar on amazon why not lol
 

systemdelete

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if you are planning on running a fridge 24/7 365 i would go ahead and pay the extra and get the solar, charge controller and a dedicated battery or two. You dont want to be stranded because a fridge and other electronics sucked all the juice from your starter batteries.
If you plan on just using the fridge while driving and overnight youll likely be fine with what you have unless your batteries are going bad.
The ARB fridge and the victron charge controller feature battery voltage protection. They will turn off the load at a set voltage. I logged data for over a year with a single X2 battery and the victron and NEVER had the voltage drop low enough to turn on the cut. A dedicated battery for a fridge alone is a waste on must rigs unless they are limited in solar input, or in a particularly less sunny area. PNW comes to mind.
 
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PNW EXPLR

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So I run a 65 at fridge on the same truck. I have had some mornings in the past where it started but was close. Because of this I installed an extra battery and an isolator kit. I also purchased a 100w solar kit for the trips where I am staying put for a couple days.
RAM 2500 Custom RTT Rack Build & Other Stuff!
 
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systemdelete

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So I run a 65 at fridge on the same truck. I have had some mornings in the past where it started but was close. Because of this I installed an extra battery and an isolator kit. I also purchased a 100w solar kit for the trips where I am staying put for a couple days.
RAM 2500 Custom RTT Rack Build & Other Stuff!
Keep in mind that a 100w panel in the PNW will yield entirely different results than the same 100w panel in FL.
 
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PNW EXPLR

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Keep in mind that a 100w panel in the PNW will yield entirely different results than the same 100w panel in FL.
Thats very true. I knew it wouldn't completely support the draw but would definitely help.
 

Vinman

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I keep an Engel MT35 in the back seat of my Ram 2500 Diesel all Summer long and the truck rarely runs on the weekends and I have yet to have an issue starting it. I know it has gone 4 days many times without running the engine to recharge the batteries.
 
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PNW EXPLR

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I keep an Engel MT35 in the back seat of my Ram 2500 Diesel all Summer long and the truck rarely runs on the weekends and I have yet to have an issue starting it. I know it has gone 4 days many times without running the engine to recharge the batteries.
I don't think my fridge is that efficient. Plus I do a lot of solo tripping. It would suck to get stranded with a dead battery in the middle of no where.
 

Vinman

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I don't think my fridge is that efficient. Plus I do a lot of solo tripping. It would suck to get stranded with a dead battery in the middle of no where.
You could always pick up a little booster pack in the event you run the batteries down. I carry an Anti Gravity power pack in my jeep at all times and they make a slightly larger version capable of starting the larger diesel engines. The smaller pack I carry is not much bigger than a smart phone, the bigger one is about twice the size.
 

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I’m wanting to run a fridge in my truck all the time. It’s a 2018 ram 2500 6.7 Cummins. The truck comes from the factory with two batteries and a 220 amp alternator. With that in mind, would solar panels be necessary to insure the truck starts every morning? About how long would the truck have to run to top off the batteries after running a fridge all night?
Do you know if the batteries are isolated from each other? Especially when the engine is off? That might give you an entirely different direction for power and the solar, etc.
 

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I usually have a fridge running in the back tub and sometimes will run two fridges when touring with my better half.
There plenty of info on how to set up either on the OB forums or with a bit of Google-foo but here’s mine....
I have two 120A dry-cell AGM battery’s under the hood. One is the primary starter the other is an auxiliary but the auxiliary can be switched to be the starter if needed. I have a Redarc Bcdc1240d Dual Battery Isolator System so both batteries receive the correct level of charge from the alternator but will protect the starter from being drained. I then have a couple of solar panels- one permanently bolted on top and one portable. Because permanent one is mounted flat it’s not set at the right angle to reach an optimum power output. Finally I have a second 110amp auxiliary AGM in an Arcpak portable power box if I’m setting up camp away from my truck and running a fridge from there or if I’m traveling with two fridges.
Hope this helps and good luck
 
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Cummins_Overland

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In a diesel both batteries are necessary for cranking the engine due to the high compression ratio. It would be best to either run deep cycle AGM batteries or in our case do a tri battery set up where the 3rd battery is just the auxiliary for running the fridge and other electronics.
 

Salty4Life

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In a diesel both batteries are necessary for cranking the engine due to the high compression ratio. It would be best to either run deep cycle AGM batteries or in our case do a tri battery set up where the 3rd battery is just the auxiliary for running the fridge and other electronics.
Where did you mount the third battery?
It seems like a goal zero plugged into a 12v charger would be the easiest way to get power. I don’t know what a battery isolators costs.
 

Cummins_Overland

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Where did you mount the third battery?
It seems like a goal zero plugged into a 12v charger would be the easiest way to get power. I don’t know what a battery isolators costs.
Honestly I didn't opt for a 3rd battery, the cost of doing such a thing didn't out weigh the cost of just buying a goal zero and running 12V power into the truck bed. If our case goal zero and a 12V charger is definitely the way to go.
 

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I wouldn't dream of running any house circuits from the starting battery(s). Use a seperate battery.
Solar panel can be used to charge the house battery along with a split charge system from your alternator, which is basically a big assed relay.
Hooking up to mains power over night is a great idea IF you are anywhere near a mains supply, most times when you are traveling....you ain't.
 

Salty4Life

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Honestly I didn't opt for a 3rd battery, the cost of doing such a thing didn't out weigh the cost of just buying a goal zero and running 12V power into the truck bed. If our case goal zero and a 12V charger is definitely the way to go.
What size did you go with? I’m torn between the 150 and 400