A pressure relief valve is a safety device designed to protect the compressor from over - pressure situations. Its primary function is to open automatically when the pressure inside the compressor reaches a pre - set limit, allowing excess air to escape and reducing the pressure back to a safe level.
[pdf] Check the isolation of the motor windings. Should be in the mage-ohms (you need an isolation tester / high voltage ohm meter for this). Check the voltage when the compressor is running. If the voltage drop significantly when the compressor starts/runs, you have a bad connection somewhere.
[pdf] Install the valve with proper positioning of the flow arrow. Support and align adjacent piping and the vale. Install lubricated flange bolts. Hands tighten, and then torque the bolts using the crossover flange bolt-tightening method to load the bolts evenly, and eliminate concentrated stresses.
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