Either an electrical problem, or the compressor has tripped on a safety device. Check supply power. Check for errors on display. Check emergency stop is out. Check and reset the overload relay. If it's a new installation, check the phase sequence.
[pdf] Each screw machine must be equipped with a gas storage tank and, if needed, auxiliary equipment such as a cold dryer and a filter. The installation requirements are as follows: A) The installation sequence of supporting equipment is: “air compressor → gas tank → gas-water separator → cold dryer.”
[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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