APU Tri-pac not charging batteries

Quick way to check the batteries. After running a few hours, lay hands on the ends if the batteries one by one & see if one of them is warmer than the others, that would be the bad one. Jus' tryin' to think.

 

I've had similar problems, and the last time they replaced the alternator, they had the new one on, and it showed that it was not charging! But the problem wasn't the alternator, the entire unit did not have a good electrical ground! So they ran a seperate ground cable from the unit to the frame rail, and now I have seen higher voltages when it is running than I ever had b4.
I also had a starting problem, that they solved by running a ground cable from the block to the frame box inside the unit, so I guess I should have thought along the same lines for the charging system.

 

I had the same problem with my APU...it was a loose connection to alt. However, I am having issues with the charging cap. Currently have a 2500 converter which runs 900 watt Micro, Ref 1.2amp, Direct TV receiver, and some times charging laptop. I seldomly use the Microwave...so I am not max out the conv...this THREAD has help. Need to go thru a process of illimination.
1. Checking the batt conditions - installed 2008 .
2. Conv is a knock off not sure if its working properly...prob buy a btr one.
3. APU is charging as per specs...may be upgrade, TK wants $560 to install 120amp...for alt and special wiring harness req.
4.

 

If the issue with my elec needs is battery replacement...can deep charge batteries be installed? Are they available for big rigs? Seems that if we are constantly charging and depleting the batt, normal batt might not last as long...can someone share some light?

 

yes something loke an Optima battery would be better for this kind of situation. They look like just the thing for this kind of application.......until you see the price! You could buy more than a few standard batteries to use and abuse for the price of 1 Optima.
With around 7000 hours on my TriPac, I put on my 6th revised model alternator! And perhaps the biggest improvement is something that they did when installing this one with the settings on the unit. They raised the low voltage limit for when the unit comes on to 12.6 volts. So the batteries do not get drained as much, which is better for them, and the alternator does not have to work as much or as hard to replentish the charge. Over another 1000 hours later it seems to be holding up.

 

Factory setting for the tri-pak are usually set at 12.2 volts, which is usually lower than than the factory setting for the truck to start shutting stuff off. I sometimes have the same issue when the truck sits longer than normal. Just before the fall, my batteries finally gave up and would discharge so rapidly that they would be to dead to start the tri pak

 

I think that is what mine was set to originally too, and when the bunk heater would cycle late at night, it would trip the low voltage alarm in my Volvo waking me up, then the TriPac would come on! So they then set it at 12.4. They brought it up to 12.6 just after the last go round with the latest alternator.

 

I run 4 Deep cell Batts. Also run 2500 Inverter, and a Slow cooker, Fridge, Computer etc. My batts seem to be fine for 20 hours or so. I shut the inverter off when I am on a full weekend out of my truck.