T-30 cycling issue
T-30 info plate
First, thanks for this forum. So much great information. As it goes I'm having a problem. I've done some research and it appears to be a check valve, but since I've had zero experience with large compressors I figured I'd put it up and see what you all think.
My t-30 starts regularly with zero issues.
Occasionally as it fills there's a knocking noise but it settles after a while. I can bring it up to 150 and it holds fine, start working and everything's great.
Here's where the problem is, if it starts running down to around 110 psi it acts like it's going to start up. The motor hums and the wheels jerk, the belts will start slipping but the unit won't kick on to build pressure. If I continue to run it the breaker will trip. If I let it run down to under 100 say 90PSI and manually turn it back on it will start and build pressure no problem.
There appears to be a nut on the center pipe running to the tank that has a hole in it to relieve pressure. Air will occasionally blow out of there where the unit is almost full or when it won't start during a cycle.
If it's a check valve, where would I find that in the unit?
Can anyone direct me how to lower the pressure to have it cycle, say to 95? That would alleviate the immediate issue and allow me to get to it later (which would be great considering everything I've got going on).
Thank you in advance!
Attached pics for reference.