Dead Batteries When Using Bunk Heater

-37C here, if heater fails I use trusty 12V electric blanket. This was awesome and lasted years with little draw on batteries. But a fair bit of frost will have blanketed your interior when you wake up…fire up truck for hour and frost willl disipate.

 

I have 8 batteries. Bunk heater should draw from auxillary batteries not start.
I have developed same issue as you though.
I can run my heater for a out 36 hours. Somewhere along that time I get low voltage disconnect. Then later heater ####s off.
But auxillary batteries still at full charge.
2 battery management systems that should not allow this.
But I can tell you this. When mine will not start it is usually dirty cable connections on auxillary.
But this new problem is different. I had 1 bad start battery. Replaced it. Everything worked good for about 1 1.2 days running [ it is just sitting and I run heater to keep gel mattress from freezing up ].
Now the charger hooked to start batteries says I have a bad battery.
So I'm thinking you should charge batteries and then have them checked .

 

How my TriPac Envidia EPU works is it will drain the truck batteries at a percent of the EPU batteries. I noticed with AC it works better than when using the bunk heater installed. Now it will just drain my truck batteries and not hardly touch the EPU batteries. So it may be by design on how the system works.

 

Exactly. I have no idea why mine is draining start battery.
I t should not and used to not. But since replacing 1 bad battery it does run all day and most of night before stopping. That is eith a 2 amp charge going to it. But I think I still have 1 more weak battery as when it shut off my charger also did and reported a bad battery. I know 1 more was weak , should have replaced it also. QUOTE="Siinman, post: 12258810, member: 194693"]How my TriPac Envidia EPU works is it will drain the truck batteries at a percent of the EPU batteries. I noticed with AC it works better than when using the bunk heater installed. Now it will just drain my truck batteries and not hardly touch the EPU batteries. So it may be by design on how the system works.[/QUOTE]

 

Actually a bunk heater should run for well over 2 days 24 hours a day . Only a tiny fan blowing. Probably not much more amps than a radio and running lights being on.
I have a generator and charger on my truck just in case of battery problem. Also putting in long jumper cables that will reach from passenger side batteríes to driver start batteries since auxillary don't go dead .

 

Atwood's has a 400.00 toolbox . Lay on side with lid up. A 1200 watt Honda generator fits right inside.
Just for jumping you could use a much smaller generator .

 

I run all sorts of stuff in cab and a little fan that draws way to much energy. I just found a new fan gonna try out with a friendly motor. If I dont use my fan it has no problems keeping up.

 

I have this and it works great. I keep it charged at all times and in the truck just incase ever needed.
NOCO Boost X GBX155 4250A 12V

 

Have you actually tried that on a semi-truck? If it has worked, that’d be an impressive unit.

 

Yep have used it once. Works like a charm.