Symptoms And Parts To Inspect - Panasonic U-36PE1U6 Technical Data & Service Manual

4-2. Symptoms and Parts to Inspect

Remote
Alarm
controller
contents
alarm display
P03 Abnormal discharge
temperature
• Discharge temp.
detected at or
above the specified
value.
High pressure
P04
switch is activated.
Compressor motor
thermal protector is
activated.
P05 Missing phase
detected. (CT
disconnected or AC
power trouble)
Insufficient gas level
P15
detected.
P19 4-way valve locked
• Judgment occurs
after compressor
has been ON for 5
minutes.
High-pressure
P20
protection trouble
P22 Outdoor unit fan
motor trouble
• Inverter protection
circuit was
activated, or lock
was detected, at
outdoor unit fan
motor.
Inverter protection
P26
circuit was
activated, or G-Tr
short-circuit (short
time: 0.8 s or less)
in inverter control
Judgment condition
Stops when temp. exceeds
232 ˚F.
Stops when pressure
exceeds 600 psi.
Stops when temp. exceeds
230 ˚F.
Current value sent from MDC
on outdoor unit control PCB is
low.
No AC power input for 3
minutes or longer: pre-trip - 5
The following conditions
continue for 1 minute.
• Discharge temp. is 203 ˚F or
higher.
• Electronic control valve is at
step 480.
• Current value from MDC is
2.0 A or less.
Indoor heat exchanger temp.
drops although compressors
are ON in heating mode:
[min(E1, E2)] ≤ 50 ˚F.
Indoor heat exchanger temp.
rises although compressors are
ON in cooling mode:
E2 ≥ 104 ˚F.
If MAX (C1,C2) is 142°F or
higher, the compressor stops
one. The compressor restarts
three time, and if the
temperature does not
decrease to less than 142°F,
the alert "P20" is displayed.
Inverter stops after alarm is
detected
Inverter stops after alarm is
detected. Alarm is output
when inverter stops (pre-trip)
consecutively 4 times.
4-5
4. Service procedures
Judgment and
Clear condition
Recovery at restart
1. Check refrigerant cycle
(gas leak).
2. Electronic control valve
trouble
3. Check tubing sensor (TD).
Recovery at restart
1. Check the high pressure
switch connector is
securely connected.
2. Check the ourdoor unit heat
exchanger is not clogged
(cooling operation).
3. Check the indoor unit air
filter has not become
clogged (heating operation)
Recovery at restart
1. Check R/S/T power.
2. Check inverter control PCB.
3. Check outdoor unit control
PCB.
Recovery at restart Check refrigerant cycle
(gas leak).
Recovery at restart
1. Check 4-way valve.
2. Check 4-way valve wiring.
3. Check outdoor unit control
PCB.
Recovery at restart
1. Refrigerant cycle
overload operation
2. Outdoor coil temperature
sensor C1 or C2
Recovery at restart 1. Position detection trouble
2. Overcurrent protection
circuit at outdoor unit fan
motor was activated.
• Check outdoor unit control
PCB.
• Refer to outdoor unit fan
judgment methods.
Recovery at restart 1. Stops immediately when
restarted.
• Layer short in the
compressor
2. Check inverter control
PCB.
• Wiring trouble
correction
4