Piloted unloader valves are used in constant run applications where there are no intake unloaders present. They incorporate a discharge unloader on the body of a pilot valve to allow one valve to sense system pressure and vent discharge air to the atmosphere when the compressor reaches maximum pressure. At the minimum PSI (110) the pilot valve closes the discharge unloader and the compressor returns to normal operation. This valve can be adjusted 30-40 +- PSI if needed. This valve fits these Rolair models: 3095K18CS, 4090HK17, 5520K17CS, 5715K17CS, 5GR30HK17, 6590HK18, 6820K17CS, 7722HK28, 8422HK30, GD4000PV5H, GD4500PV5R, & 5GR SERIES.
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