35
E7
(
air discharge temp. sensor loose error)
Diagnosis
Handling
Check whether the sensor
doesn’t fix to discharge pipe
No
Check if wiring of T3
，
T5
sensors and pressure sensor
are in accordance with wiring
name plate
Yes
Check if there’re other heat
sources around T3
，
T5
No
Whether resistance of T5 is in
the range of TABLE2
Yes
Power off and restart to see
if there’s the same error
Fix air discharge temp.
sensor to the air
discharge pipe, re-power
on to start the unit
Yes
Wiring according to the
nameplate and re-power
on to start the unit
No
To troubleshoot
influences by surround-
ing heat sources
Yes
Replace T5 temp. sensor
No
Replace the mainboard
Yes
H3/P3
(
Frequency-conversion over-current protection)
Diagnosis
Handling
If ball valves are open
Yes
If compressor wiring is normal
Yes
Whether compressor insulation
resistance is below 100k
Ω
Yes
Restart after powering on to
make sure that high and low
pressure difference is within
0.2MPa
Yes
Power off and restart to see
if there’s the same error
Open gas valve and
liquid valve
No
Wiring according to the
nameplate and re-power
on to start the unit
No
Compressor exchange
No
Start after pressure balance
or if system can’t balance
pressure in 10min, then the
refrigerant system is error
No
Replace the mainboard
Yes
H5/P2
(
Low pressure protection)
Diagnosis
Handling
Whether gas valve and liquid
valve are open
Yes
Whether indoor side is normal,
valve is blocked or radiator is
sheltered, fan is stopped
No
Unplug low pressure sensor
LPC to see if resistance is 0
Ω
(0
Ω
is normal)
No
Connect a pressure gage to
gas valve and restart to test
if pressure is less than
0.3MPa
Yes
Check if refrigerant system
is lack of refrigerant
according to refrigerant
filling table
No
Power off and restart to see
if there’s the same error
Open gas valve and
liquid valve
No
Exclude inside reasons
and restart
Yes
Replace the mainboard
Yes
Filling refrigerant and
restart
Yes
Replace low pressure
sensor
No
Replace the mainboard
Yes
F5/Hb
(
Heating high pressure protection)
Diagnosis
Handling
Whether gas valve and liquid
valve are open
Yes
Whether indoor side is normal,
valve is blocked or radiator is
sheltered, fan is stopped
No
If air return temp. of the indoor
side is over 35
℃
No
Whether outdoor side
ambient temp. is over 30
℃
No
Whether outdoor unit EV is
sticking.(C)
No
Restart to see if there’s the
same error
Open gas valve and
liquid valve
No
Exclude indoor side error
Yes
Troubleshooting. e.g.
indoor side E-heat or
other heat sources are
overheat
）
Yes
Replace EV of outdoor
unit
Yes
Not applicable to start
heating
Yes
Keep on operating
Replace the mainboard
Yes
No
