THERMO KING TRI PACK APU heater wont work

What makes a trip pack turn on and work the heater properly but when it turn off and then restarts on its own the heat wont blow out I have to shut off the apu and restart it when I get cold enough to wake up

 

my webasto heater doesn’t work after I am change the alternator from apu,Somebody know what’s going on

 

webasto doesn’t work after Im change the alternator from apu, somebody know what’s going on

 

Try restarting it a bunch of times. Often times in the cold even with anti gel the fuel lines in the apus are really small and get frozen up but if you turn it off and on a bunch to keep priming it, it can start working again. Think of it like yanking a pull start on a portable generator. Sometimes you gotta yank it a few times before it gets going. Worked for me at least