MCAC-RTSM-2013-12 Midea High-temperature Direct-heating Heat Pump Water Heater Technical Manual
44
6. Error Code Cause Analysis and the Solutions
Power phase
sequence failure
Reverse-connection of the unit three-phase
supply line
Exchange the two supply lines after
power off.
One phase or two phases are not connected
well
Connect the supply line well after
power off.
Communication failure between the main unit
and the wire controller.
Correct connection between the main
unit and the A, B, P, Q and E lines of
the wire controller.
Communication failure between the main unit
and the wire controller, slave unit failure
P, Q and E lines correct connection
between the slave unit and the main
unit, no connection of the A and B lines.
Electromagnetic interference because
communication line is not the shielded line
Replace the communication line with
the shielded line.
Outlet water
temperature sensor
failure
The water port between the sensor and the
main board is loose
Water temperature
sensor in the water
tank failure (the unit
can also be start up,
but only for the
directly-heating type)
The T5 port between the sensor and the main
board is loose
Condenser
temperature sensor
failure
The T3 port between the sensor and the main
board is loose
Outdoor ambient
temperature sensor
failure
The T4 port between the sensor and the main
board is loose
Electric-heating pipe
temperature sensor
failure
( RSJ-380/SN1-820-
D)
The T6 port between the sensor and the main
board is loose
Water inlet temp.
sensor error(T7
temp.)
The T7 port between the sensor and the main
board is loose
Exhaust temp.
sensor error(TP
temp.)
The Tp port between the sensor and the main
board is loose
System low pressure
protection
Check the motor of the fan.
Check the leaking place, mend by
welding, drawing out the air and add
refrigerant again.
System high
pressure protection
Deficient circulating water
pump flow use
RSJ-380/SN1-820-D flow should be ≥
6 m
3
/h;
RSJ-200/SN1-540V-D flow should be
≥ 4 m
3
/h;
RSJ-100/N1-540V-D flow should be ≥
2 m
3
/h.
Circulation pipeline filter is dirty
and blocked
The water pump doesn’t work
Check the operation of the warm water
valve.
Bad bypass solenoid valve
operation and lack of water
flow PTE
Check the bypass solenoid valve.
Check the operation of the warm water
valve.