Model 77813 Pressures up then shuts down and opens relief valve
Model 77813 Pressures up to about 120 psi then the motor cuts off, the pressure relief valve is activated and the pressure drops to about 100 psi.
At this point, the relief valve closes, holding the pressure at 100 psi.
Then the motor hums for about 5 seconds, cuts off and the reset button pops out. Motor will not start back up until all the pressure is relieved and the reset button is pushed. Then I can turn the switch off and on and the whole process starts again.
Gary, when you say "the pressure relief valve is activated" I need to be sure that you are referring to a PRV and not the unloader valve?
I cannot locate a picture of your compressor.
So, the PRV typically has a ring on the end of it to manually open it, and the unloader valve is, again typically, part of the pressure switch.
To which are you referring?
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