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ESI Outdoor Unit Installation Instruction
05.2018
Manufacturer reserves the right to change at any time for specifications or designs without notice and incurring obligations.
Abnormal switch alarm for 4-way valve
1.Error definition:
4-way valve switch incompletely after defrost operation or from cooling mode.
If TH ≥ TL+5.4F and TH ≥ TA+5.4F, report this alarm.
2.Possible causes:
Damaged 4-way valve
Damaged main control board
Abnormal voltage of power supply(too low voltage)
Temperature sensor(TH) failure
4-way valve is set up power on when cooling mode.
Display
YES
NO
Is the output on connector CN14 (4-way valve) 220VAC in
heating mode?
Replace the main control board
Is the gas pipe close to service valve hot?
NO
YES
Check whether TH temperature
sensor is failed.
Change the coil of 4-way valve and restart the system, does the
problem remain?
YES
NO
Normal control
Recover the refrigerant and replace the 4-way valve body
NO
YES
The power supply voltage is less than 175VAC.
Contact agency supplying power
to verify that they are sending the
correct voltage.
Replace the main control board, is the alarm disappears?
NO
YES