842 StarCool Alarm Codes

842	Expansion valve
Description	Expansion Valve Fault
Cause	Indication of non-operating electronic expansion valve
Trouble shooting	Possible causes: Cable for expansion valve mounted on wrong valve. Cable for expansion valve defective. Expansion valve defective. Driver circuit for expansion valve defective. Trouble shooting: Try to correct the error by uploading the latest software version to the controller. If there is more than one valve failure, the cables for the valves are presumably switched. Mount cables for valves on the correct valve. Listen if the expansion valve is opening and closing. If not, then go to 4) If the valve is opening and closing, close service valve (pos. 14 P-I diagr.) Run FT again. If the test now is a pass, the expansion valve is defective and should be replaced. Check that the cable for the expansion valve is not defective. Replace cable if it is damaged. Disconnect the cable for valve and measure that there is voltage on the output for the expansion valve when it should open. a. If there is no voltage, the main controller is defective. Replace the main controller.
Criteria	Pdis more than (>) 5 BarE: Max change on Pdis: ±0.75 Bar Pdis is less than (<) 5 BarE: Max change on Pdis: ±0.30 Bar Tret more than or equal (≥) to -15°C: Min change on T0: +20°K Tret is less than (<) -15°C: Min change on T0: +10°K