Will a plug in cooler kill your battery?

That's what I was going to say. Some trucks have 3 and some 4 batteries. It makes a big difference with 25% more reserve. It's been years since I had one of those things but I don't remember it draining my batteries. I think you can get about 8 hours before you start pushing it with 4 batteries.

But don't forget trucks have a low voltage shutdown. When the batteries get around 11V an alarm will sound and a relay will kick shutting down the system. You usually have just enough juice left to get the truck started then.

Invest in a good set of 4 AWG 16-20 foot jumper cables and keep them on the truck. If you don't need them you might be able to help someone else out. Notice there is a jump hot post on the firewall in front of the driver.

 

Not every truck has that function, but you can get a voltage indicator to plug into the accessory outlet. Some will sound an alarm when voltage gets too low.

 

Flatbed I do always have phone, Bluetooth , and Qualcomm on.

 

What are you in? A Mack?

I've had Freightliners, Volvo's and Pete's all had it. Back in the old days didn't.

 

My old '04 International would kill batteries with the bunk heater. My current '07 387 starts beeping too soon.

 

I have a DC truck fridge in the sleeper and its hard wired to the fuse box, so it uses very little power. In fact I could shut the truck down for a full day and a half and it wouldn't drain the batteries. The only way your cooler would run them down is if the batteries are not in good condition and lose their charge easily.

 

The fans are what goes bad you can get them at any computer outlet. And the just plug right into the same plug. Had my coleman for 3 years had to replace the inside fan 2 time because the fans aren't designed to run with water condensation

 

i run a dashcam, a rand mcnally 520, a 12v 40 qt cooler, and a cell phone charger and a laptop charger with a 12v power inverter.

i can run the 12v cooler and my 12v phone charger all night and never get woken up by the battery rundown protection alarm.

but i also have to unplug everything else, otherwise its beep beep beep about 5 or 6 hours into my sleep period and thats annoying.

also most trucks have a battery rundown protection feature where it will stop pulling juice from the battery if it goes below a certain level and it turns off all the 12v outlets and power sources. this ensures you have enough juice to start her up in the morning.

 

Need to also keep in mind that most of these Peltier Thermo Electric Coolers (Koolatron, Coleman etc) weren't designed to run 24/7. Mine runs during my drive and I leave it on until I hit the bunk. I wired a toggle switch so all I have to do is flip it and I shut it down until I get back up. Everything stays cold, nothing gets spoiled and it increases the life of both the cooling unit and the fan. Mines going on 2 years now and still runs like a champ.

However, the next time I get a load going by Georgetown KY, I'm going by the Truck Fridge outlet and finally getting a compressor driven model like a Dometic.