Panasonic CS-VZ9SKE Service Manual page 103

H96 2- and 3-way valve
opening failure check
H97 Outdoor unit fan
motor lock error
H98 Indoor unit
overpressure
protection
H99 Indoor unit heat
exchanger freezing
protection
F11 Cooling-Heating
switching error
F19 Aluminium Electric
Heater (Heatcharge)
wire cut abnormality
Failure to open the 2- and 3-way valve is detected based on the changes in indoor unit
intake air temperature and indoor unit pipe temperature. The time required for this
detection is approximately 10 minutes when in COOL mode and approximately 25
minutes when in HEAT mode.
<Points of diagnosis>
1. Check if the 2-way and 3-way valves are closed.
If a rotation error (too high/low speed) is detected for 10 consecutive seconds, only the
fan motor is stopped and then restarted. If the rotation error is detected 2 consecutive
times or if an overcurrent (fan motor current 3A and above) is detected, the compressor
is stopped, and then restarted after 180 seconds. If the error or overcurrent is detected
two times within 20 minutes, this error code is displayed.
<Points of diagnosis>
1. Check for outdoor unit fan motor lock.
2. Poor contact and detached fan motor connector, fan motor failure and outdoor unit
control board.
When the temperature of the indoor unit heat exchanger temperature sensor exceeds
60°C during the heating operation, this diagnosis code is stored in the memory and the
compressor stops operation. It resumes operation after 180 seconds if the temperature
is below 60°C. No error code is displayed.
<Points of diagnosis>
1. Check of the indoor unit heat exchanger temperature sensor (Check for change in
characteristic and resistance value): Symptom – No hot start, no thermo ON and
repeating stop and start during the start of the operation.
2. Additional check for short-circuit of the indoor unit and clogging of air filter.
When the temperature of the indoor unit heat exchanger temperature sensor is 0°C for 6
consecutive minutes during the cooling or dry operation, this diagnosis code is stored in
the memory and the compressor stops. It resumes operation after 180 seconds if the
temperature is 10°C and above. No error code is displayed.
<Points of diagnosis>
1. The primary cause is cooling or dry operation at low outside temperature. This is not
a failure. H99 is also displayed if dry operation is performed under AUTO mode in
winter while the outside temperature goes up.
2. Check of refrigerant cycle: Gas leak (refrigerant level is low) and pipe breakage.
3. Additional check for short-circuit of the indoor unit and clogging of air filter.
When the temperature of the indoor unit heat exchanger temperature sensor after 4
minutes from the start of compressor is 45°C and above during cooling or dry cool
operation or below 0°C during heating operation, this diagnosis code is stored in the
memory and the compressor stops. It resumes operation after 180 seconds. The error
code is displayed if this error is detected four times within 40 minutes.
<Points of diagnosis>
1. Check of the 4-way valve: Check for disconnection or short-circuit of the 4-way valve
coil.
2. If the 4-way valve is normal, then switching error of the 4-way valve has occurred.
When the total electric current value is judged to be abnormal after Aluminium Electric
Heater (Heatcharge) is switched ON during 6-12 seconds after switched on the outdoor
unit.
<Points of diagnosis>
1. Check the Aluminium Electric Heater (Heatcharge) PCB: in-motion temperature:
160°C, revert back temperature: 125°C.
2. Check temperature fuse Aluminium Electric Heater (Heatcharge) power source:
In-motion temperature heat fuse at 129°C, Aluminium Electric Heater
(HEATCHARGE) power source wire cut at 240°C.
3. Check PCB: only check Aluminium Electric Heater (Heatcharge) PCB: change PCB
if open.
103
 2- and 3-way valve
opening failure
 Outdoor unit control
board
 Outdoor unit fan
motor
(Bad connection /
detached
connector)
 Dirt on air filter
 Short-circuit of
indoor unit
 Low refrigerant
level (relatively
low)
 Dirt on air filter
 Short-circuit of
indoor unit
 4-way valve
 4-way valve coil
 Aluminium
Electric Heater
(Heatcharge) PCB
(wire cut)
 Temperature fuse
(wire cut)
 Outdoor unit PCB