Sinclair SCV-EB Series Service Manual page 60

5.16 H7 Troubleshooting
5.16.1 Digital display output
5.16.2 Description
 H7 indicates Voltage protection
 Heat pump stops running.
 Error code is displayed on the refrigerant system PCB digital tube and user interface..
5.16.3 Procedure
Power supply voltage is not within ±10%
of rated voltage or a (on 3-phase models)
Wires between refrigerant system PCB,
AC filter board (on 3-phase models) and
electric control box power supply
terminals are loose
Outdoor unit powered on immediately
after being powered off
High voltage circuit error has occurred,
such as the compressor has
malfunctioned, the fan motor has
short-circuited, or the inverter module
has short-circuited
Replace refrigerant system PCB
58
H7
phase is missing
No
No
No
No
Yes
Provide normal power supply
Yes
Ensure the wires are connected properly
Power-off the unit and wait for at least 3
Yes
minutes before powering-on
Yes
Replace or repair the relevant parts