Lennox LIAC024-180P431, Руководство по установке

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29
C5/E7
(
Compressor discharge sensor(T5) is seated fault)
Diagnosis Handling
Check whether the sensor is
not seated on the discharge
pipe
No
Check whether wiring of T3
/
T5
sensors and pressuretransduce
(PT) are wired in accordance
with wiring name plate
Yes
Check whether there’re other
heat sources around T3
，
T5
No
Check whether resistance of
T5 is in the range of TABLE2
Yes
Power off and restart to see
whether there’s the same fault
Fix discharge temp.
sensor to the compressor
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
(
Compressor over current protection)
Diagnosis Handling
Check whether the service
valves are open
Yes
Check whether compressor
wiring is normal
Yes
Check whether compressor
insulation resistance is below
100kΩ
Yes
Restart after powering on to
check that whether high and
low pressure difference is
within 30 PSI
Yes
Power off and restart to check
whether there’s the same fault
Open the service 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 fault
No
Replace the mainboard
Yes
H5/P2
(
Low pressure(PT) Protection in cooling)
Diagnosis Handling
Yes
Check whether indoor unit is
normal, valve is blocked or
filter is sheltered, indoor airflow
is normal
No
No
Connect a pressure gage to
suction valve and restart to
check whether pressure is
less than 45PSI
Check whether refrigerant
system is lack of refrigerant
according to subcooling in
charge model (force mode)
No
Power off and restart to
check whether there’s the
same fault
No
Exclude indoor unit fault
reasons and restart
Yes
Yes
Filling refrigerant and
restart
Yes
Replace pressure transducer
No
Replace the mainboard
F5/Hb
(
High pressure(PT) protection in Heating)
Diagnosis
Handling
Yes
No
Check whether the indoor air
inlet temp is over 86°F
No
Check whether outdoor side
ambient temp. is over 86°F
No
Check whether outdoor
electric expland valve is
sticking.(C)
No
Restart to check whether
there’s the same fault
No
Yes
Troubleshooting. e.g.
indoor side E-heat or
other heat sources are
overheat
）
Yes
Replace electric expland
valve of outdoor unit
Yes
Not applicable to start
heating
Yes
Keep on operating
Replace the mainboard
Yes
No
Check whether the service
valves are open
Open the service valve
Check whether the service
valves are open
Open the service valve
Check whether indoor unit is
normal, valve is blocked or
filter is sheltered, indoor airflow
is normal
Exclude indoor unit fault
reasons and restart