TriPac APU Starts, runs for 30 seconds, then struggles.

Is it the older style Tri pac?. Or evolution,
If older style turn throttle screw in to increase rpm about 100 rpm. Will not hurt the unit. It will not struggle as much and A/c compressor will turn a tad faster. Also is air filter clean?.
A/c compressor puts a big strain on unit.
Before anyone says it will hurt the unit. No it won’t thermo king dealers do it all the time on older non evolution APU

 

is this only on cold starts. if so, start it on fan mode only. warm up engine and then turn to ac

 

Why would you change oil and filters every month?

The chances are, you have a problem in the fuel supply. Fuel poseibly draining back into the tank. Does your electric lift pump work? Itcstarts clicking about two seconds before the unit starts.

 

idk. i was just thanking of something

 

I would like to know if there was a conclusion? I would suspect the A/C system is overcharged?? Liquid collecting at the bottom (the pump) like liquid does, at start-up the pump has to move the liquid along, that's hard on the pump, it would bog the engine until the excess liquid is gone back up in the system???