Checkout Current Transformers (CTs) and check resistance across each one while it is disconnected. All resistances should be within 10% of one another. Also do a diode test on the CT inputs on each compressor module. (The diode test is described in RTAA-SVB10B-EN.)
[pdf] Disassemble the air compressor cylinder head. Refer to Procedure 012-106. Use a coupling puller, Part Number 3376663, or equivalent, to remove the spline coupling hub. Remove the front thrust bearing. Remove the three flange head capscrews. Remove the three captive washer capscrews.
[pdf] Before making any repairs, be sure the unit is unplugged and tank has no air. To remove the line and load cords from the pressure switch, the pressure switch cover will need to be removed. Use your Phillips head screwdriver to loosen the screw located either on the top or on the side of the cover.
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