Mitsubishi Electric PUHZ-HRP71VHA Service Manual page 48

Error Code Abnormal point and detection method
Freezing/overheating protection is working
Overheating protection <Heating mode>
Abnormal if condensing temperature of
pressure sensor (63HS) detects
Tcond. : or more and compressor
operation frequency is less than or equal
to 25 Hz. Detection is inoperative during
defrosting.
Tcond
P6
stage-g
Pipe temperature
<Cooling mode>
Detected as abnormal when the pipe
temperature is not in the cooling range
3 minutes after compressor start and
6 minutes after the liquid or condenser/
evaporator pipe is out of cooling range.
Note 1) It takes at least 9 minutes to detect.
Note 2) Abnormality P8 is not detected in
drying mode.
Cooling range : Indoor pipe temperature
(TH2 or TH5) – room temperature
(TH1) [ -3 :
TH: Lower temperature between liquid pipe
temperature and condenser/evaporator
temperature
P8
<Heating mode>
When 10 seconds have passed after the
compressor starts operation and the hot
adjustment mode has finished, the unit is
detected as abnormal when condenser/
evaporator pipe temperature is not in
heating range within 20 minutes.
Note 3) It takes at least 27 minutes to
detect abnormality.
Note 4) It excludes the period of defrosting
(Detection restarts when defrosting
mode is over)
Heating range : 3 : [ (Condenser/
Evaporator temperature(TH5) –
room temperature(TH1))
Abnormal refrigerant circuit
During Cooling, Dry, or Auto Cooling
operation, when the following are
regarded as failures when detected for
one second.
a) The compressor continues to run for 30
PL
or more seconds.
b) The liquid pipe temperature or the
condense/evaporator temperature is
75°C or more.
* These detected errors will not be
cancelled until the power source is reset.
OCH425F
1 Overcharge of refrigerant
2 Defective refrigerant circuit
3 Malfunction of linear expansion valve
4 Reduced water flow
5 High temperature
6 Defective water pump
* 4~6 is in the case that the unit
stage-e
stage-f
-18 -17 -15 -14 -12 -11
stage-a
Tcond
63
PUHZ-HRP100VHA2R2 : 61
1 Slight temperature difference
2 Converse connection of
3 Converse wiring of indoor/
4 Defective detection of indoor
5 Stop valve is not opened
1 Abnormal operation of 4-way
2 Disconnection of or leakage in
3 Air into refrigerant piping
4 Abnormal operation (no rotation)
5 Defective refrigerant circuit
Case
(clogs)
· Clogged filter
· Leakage of water
· Over-load
· Inlet water is too warm.
is used as Air to water.
stage-c
stage-d
-9 -8 -6
Ambient temperature (TH7)
stage-b stage-c stage-d stage-e stage-f stage-g
62 61 60 59
between indoor room temperature
and pipe <liquid or condenser/
evaporator> temperature
thermistor
• Shortage of refrigerant
• Disconnected holder of
pipe <liquid or condenser/
evaporator> thermistor
• Defective refrigerant circuit
extension pipe (on plural units
connection)
outdoor unit connecting wire (on
plural units connection)
room temperature and pipe
<condenser / evaporator>
temperature thermistor
completely.
valve
refrigerant pipes
of indoor fan
· Defective fan motor.
· Defective indoor control
board.
(clogging)
48
Judgment and action
12 Check operating condition of refrigerant
circuit.
3 Check linear expansion valve.
45 Check water piping.
6 Check water pump.
stage-a
stage-b
-5 -3 -2
[ ]
57 51
1~4 Check pipe <liquid or condenser/evaporator>
temperature with room temperature display
on remote controller and outdoor controller
circuit board.
Pipe <liquid or condenser/ evaporator>
temperature display is indicated by setting
SW2 of outdoor controller circuit board as
follows.
Conduct temperature check with outdoor
(
controller circuit board after connecting
'A-Control Service Tool (PAC-SK52ST)'.
Temperature display of indoor condenser/
Temperature display of indoor liquid pipe
evaporator pipe Indoor 1
Indoor 1
1 2 3 4 5 6 1
ON
OFF
Temperature display of indoor condenser/
Temperature display of indoor liquid pipe
evaporator pipe Indoor 2
Indoor 2
1 2 3 4 5 6
1
ON
OFF
A-Control Service Tool SW2 setting
23 Check converse connection of extension
pipe or converse wiring of indoor/outdoor
unit connecting wire.
1 When this error occurs, be sure to
replace the 4-way valve.
2 Check refrigerant pipes for disconnection or
leakage.
3 After the recovery of refrigerant, vacuum
dry the whole refrigerant circuit.
4 Refer to section 11-6.
5 Check refrigerant circuit for operation.
* To avoid entry of moisture or air into
refrigerant circuit which could cause
abnormal high pressure, purge air in
refrigerant circuit or replace refrigerant.
)
2 3 4 5 6
ON
OFF
2 3 4 5 6
ON
OFF