Mitsubishi Electric CITY MULTI CMB-P1016V-F, Service Handbook

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Checking code Meaning, detecting method Cause Checking method & Countermeasure
Low
pressure
saturation
tempera-
ture
sensor
abnormal-
ity (TH2) 1111 1. When saturation temperature
sensor (TH2) detects -40˚C or
less (the first time) during op-
erations, outdoor unit stops
once, mode is changed to re-
start mode after 3 minutes, then
the outdoor unit restarts.
3.
4. When -40˚C or less tempera-
ture is detected 30 or more min-
utes after stop of outdoor unit,
the stop is regarded as the first
time and the process shown in
1. is observed.
5. 30 minutes after stop of outdoor
unit is intermittent fault check
period with LED displayed.
Note:
1. Low press. saturation tem-
perature trouble is not de-
tected for 3 minutes after
compressor start, and finish
of defrosting operations, and
during defrosting operations
.
2. In the case of short/open of
TH2 sensor before starting
of compressor or within
10 minutes after starting
of compressor, “1111”
is displayed, too.
See Refrigerant amount check.
Check operating conditions and opera-
tion status of outdoor unit.
Check operation status by actually per-
forming cooling-only or heating-only
operations.
Cooling-only : indoor LEV
LEV1 (PUHY)
LEV1, 3 (BC)
SVA (BC)
Heating-only : indoor LEV
LEV3 (PURY)
(BC)
SVB (BC)
SV3~6 (PURY)
SV3~4 (PUHY-P)
See Trouble check of LEV and sole-
noid valve.
Check address setting of indoor unit
connector.
Confirm that ball valve is fully opened.
Check indoor unit, and take measu-res
to troube.
Check outdoor unit, and take measures
to trouble.
Check outdoor unit fan.
See Trouble check of outdoor unit
fan.
See Trouble check of solenoid valve.
Check resistance of thermistor.
See Trouble check of pressure sen-
sor.
Check inlet temp. and press. of sensor
by LED monitor.
1) Gas leak, Gas shortage.
2) Insufficient load operations.
3) Poor operations of indoor LEV.
4) Poor operations of OC controller
LEV:
Cooling : LEV1
5) Poor operations of BC controller
LEV:
Cooling-only
: LEV3
Cooling-main : LEV1, 3
Heating-only, Heating-main:
LEV3
Defrost : LEV3
6) Poor operations of BC controller
SVB:
Heating-only, Heating-main
7) Solenoid valve trouble (SV3 ~ 6)
(PURY). PUHY-P (SV3 ~ 4)
Heating-only, Heating-main
8) Setting error of connection address.
9) Poor operations of ball valve.
10)Short cycle of indoor unit.
11)Clogging of indoor unit filter.
12)Fall in air volume caused by dust
on indoor unit fan.
13)Dust on indoor unit heat exchanger.
14)Indoor unit block, Motor trouble.
8)~13) : Fall in low pressure
caused by evaporating capac-
ity in cooling-only cooling-prin-
cipal operation.
15)Short cycle of outdoor unit.
16)Dust on outdoor heat exchanger.
17)Indoor unit fan block, motor trouble,
and poor operations of fan control-
ler.
14)~16) : Fall in low press. caus-
ed by lowered evaporating
capa-city in heating-only heat-
ing-principal operation.
18)Poor operations of solenoid valve
SV1.
Bypass valve (SV1) can not
control low pressure drop.
19)Thermistor trouble (TH2~TH6).
20)Pressure sensor abnormality.
21)Control circuit board thermistor
abnormality and pressure sensor
input circuit abnormality.
22)Poor mounting of ther mistor
(TH2~TH6).
Lo
w pressure satur
ation temper
ature troub
le
2. When a temperature of -40
°
C
or less is detected again (the
second time) with in 30 mi-
nutes after the first stop of out-
door unit, mode is changed to
restart mode after 3 minutes,
then the outdoor unit restarts.
When -40˚C or less temp. is
d e t e c t e d a g a i n ( t h e t h i r d
time) within 30 minutes after
the second stop of outdoor
unit, error stop i s o b s e r v e d
w i t h c o d e N o s “ 1 1 1 1 , ”
“1112,” or “1113” displayed.