AAON

[chuck389]

Got stuck with a 3 year old 25 ton AAON 2 stage split with hot gas by pass.
When first stage starts pressures run about 250 head and a 70 suction,amp draw on the comp. is rated at 45 amps and runs at 48. after about 1 to 1 1/2 minutes of running the suction pres. drops and runs about 30 pounds with the aid of the hot gas bypass and the head drops to about 200 lbs and amp draw drops to 35amps. shut of the hot gas bypass and the suction will drop and shut off on low pressure. air flow is correct and the filters and coil are clean.'
2ND stage runs fine. any ideas.

[doubleduece]

Check the piping and make sure the circuits are not crossed, ie. liquid line of cir. 1 piped to liquid line of cir.2 ,etc.

[chuck389]

first thing I checked because I had a AAON piped wrong from the factory. besides 2ND stage runs fine. I am leaning more to water freezing in the TXV. It may be long shot but its best I can come up with.

[hmscool]

Hi. just started up a 2 stage 15ton unit. it has hgb and reheat. Is your charge correct?Do you have a sight glass/moisture indicator? i have a tech support phone number for them in my truck if u need it. Is the compressor really loud at 1st? 3 amps over rated seems like its working hard or maybe pumping liquid. check cch. good luck

[maxster]

did you check the LL dryer for a temp drop going to that TXV

[allstar08]

LL restriction
low on charge