Mitsubishi Electric PUY-A12NKA7, Руководство по обслуживанию

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33
<Abnormalities detected while unit is operating>
Check code Abnormal points and detection method Case judgment and action
U1
(1302)
High pressure (High-pressure switch
63H operated)
Abnormal if High-pressure switch 63H
worked (*) during compressor operation.
*602 PSIG [4.15 MPa]
63H: High-pressure switch
1
Short cycle of indoor unit
2
Clogged filter of indoor unit
3
Decreased airflow caused by
dirt of indoor fan
4
Dirt of indoor heat exchanger
5
Locked indoor fan motor
6
Malfunction of indoor fan motor
7
Defective operation of stop
valve (Not full open)
8
Clogged or broken pipe
9
Locked outdoor fan motor
0
Malfunction of outdoor fan motor
1
Short cycle of outdoor unit
2
Dirt of outdoor heat exchanger
3
Decreased airflow caused by
defective inspection of outside
temperature thermistor
(It detects lower temperature
than actual temperature.)
4
Disconnection or contact failure
of connector (63H) on outdoor
controller board
5
Disconnection or contact failure
of 63H connection
6
Defective outdoor controller board
7
Defective action of linear
expansion valve
8
Malfunction of fan driving circuit
1
–
6
Check indoor unit and repair the defect.
7
Check if stop valve is fully open.
8
Check piping and repair the defect.
9
–
2
Check outdoor unit and repair the defect.
3
Check the inspected temperature of outside
temperature thermistor on LED display.
(SW2 on A-Control Service Tool : Refer
to "10-10. FUNCTION OF SWITCHES,
CONNECTORS AND JUMPERS".)
4
–
6
Turn the power off and check F5 is
displayed when the power is on again.
When F5 is displayed, refer to “Judgment
and action” for F5.
7
Check linear expansion valve.
Refer to "10-6. HOW TO CHECK THE
PARTS" and "10-7. HOW TO CHECK THE
COMPONENTS".
8
Replace outdoor controller board.
U2
(TH4: 1102)
(TH33: 1132)
High discharge temperature
High comp. surface temperature
(1) Abnormal if discharge temperature ther-
mistor (TH4) exceeds 257˚F [125
:
] or
230˚F [110
:
] continuously for 5 minutes.
Abnormal if condenser/evaporator tem-
perature thermistor (TH5) exceeds 104˚F
[40
:
] during defrosting and discharge
temperature thermistor (TH4) exceeds
230˚F [110
:
].
(2) Abnormal if discharge superheat
(Cooling: TH4−TH5
Heating: TH4−TH6) increases.
All the conditions in A or B are detected
simultaneously for 10 minutes continu-
ously after 6 minutes past from com-
pressor Startup (including the thermostat
indication or recovery from defrosting).
<Condition A>
• Heating mode
• When discharge superheat is less than
126˚F [70
:
].
• When the TH6 temp is more than the
value obtained by TH7−9˚F [5
:
].
• When the condensing temp of TH5 is
less than 95˚F [35
:
].
<Condition B>
• During comp. operation (Cooling and
Heating)
• When discharge superheat is less than
144˚F [80
:
] in cooling.
• When discharge super heat is less
than 162˚F [90
:
] in heating.
• When condensing temp of TH6 is more
than −40˚F [−40
:
] (In cooling only).
(3) Abnormal if comp. surface temperature
thermistor (TH33) exceeds 239˚F [115
:
]
or 221˚F [105
:
] continuously for 5
monitues.
A12–30N: 257˚F [125
:
] or 230˚F [110
:
]
A36, 42N: 239˚F [115
:
] or 221˚F [105
:
]
1
Overheated compressor opera-
tion caused by shortage of
refrigerant
2
Defective operation of stop
valve
3
Defective thermistor
4
Defective outdoor controller
board
5
Defective action of linear
expansion valve
1
Check intake superheat.
Check leakage of refrigerant.
Charge additional refrigerant.
2
Check if stop valve is fully open.
34
Turn the power off and check if U3 is dis-
played when the power is on again.
When U3 is displayed, refer to “Judgment
and action” for U3.
5
Check linear expansion valve.
Refer to "10-6. HOW TO CHECK THE
PARTS" and "10-7. HOW TO CHECK THE
COMPONENTS".
OCH636A