– 60 –
Operation of diagnostic function
Check code
Status of
air conditioner
Condition
Cause of operation
Judgment and measures
Indoor unit
F04
Disconnection, short of discharge
temp. sensor (TD)
Stop
Displayed when
trouble is detected
1. Check discharge temp. sensor (TD).
2. Check outdoor P.C. board (MCC-1675).
F06
Disconnection, short of outdoor temp.
sensor (TE)
Stop
Displayed when
trouble is detected
1. Check temp. sensor (TE).
2. Check outdoor P.C. board (MCC-1675).
F07
Disconnection, short of outdoor temp.
sensor (TL)
Stop
Displayed when
trouble is detected
1. Check temp. sensor (TL).
2. Check outdoor P.C. board (MCC-1675).
F12
Disconnection, short of suction temp.
sensor (TS)
Stop
Displayed when
trouble is detected
1. Check suction temp. sensor (TS).
2. Check outdoor P.C. board (MCC-1675).
F15
Miss-mounting of outdoor temp.
sensor (TE, TS)
Stop
Displayed when
trouble is detected
1. Check temp. sensor (TE, TS).
2. Check outdoor P.C. board (MCC-1675).
F08
Disconnection, short of outside temp.
sensor (TO)
Continue
Displayed when
trouble is detected
1. Check outside temp. sensor (TO).
2. Check outdoor P.C. board (MCC-1675).
F13
Disconnection, short of heat sink
temp. sensor (TH)
Stop
Displayed when
trouble is detected
1. Check outdoor P.C. board (MCC-1675).
(Q201 is incorporated in TH sensor.)
F31
Outdoor P.C. EEPROM trouble
Stop
Displayed when
trouble is detected
1. Check outdoor P.C. board (MCC-1675).
L10
Unset jumper of service P.C. board
Stop
Displayed when
trouble is detected
1. Outdoor service P.C. board
Check model type setting jumper wire.
L29
Communication trouble between
outdoor P.C. board MCU
Stop
Displayed when
trouble is detected
1. Check outdoor P.C. board
(MCC-1698, MCC-1597, MCC-1675).
2. Connection check between CN802 of MCC-1675 and
CN505 of MCC-1597, and also connection check
between CN504 of MCC-1597 and CN852 of MCC-1698.
F23
Ps sensor trouble
Stop
Displayed when
trouble is detected
1. Check connection of Ps sensor connector.
2. Check failure of Ps sensor.
3. Check compressing power trouble of compressor.
4. Check 4-way valve trouble.
5. Check outdoor P.C. board trouble.
H06
Low pressure protective operation
Stop
Displayed when
trouble is detected
1. Check service valves are fully opened.
(Gas side, Liquid side)
2. Check clogging of outdoor PMV. (PMV1, 2)
3. Check SV2 circuit.
4. Check Ps sensor trouble.
5. Check clogging of indoor filter.
6. Check clogging of refrigerant pipe.
7. Check of outdoor fan operation. (In heating mode)
8. Check short of refrigerant.
P07
Heat sink overheat trouble
∗
Heat sink temp. sensor detected
over specified temperature.
Stop
Displayed when
trouble is detected
1. Check screw tightening between PC. Board and heat
sink and check radiator grease (MCC-1596).
2. Check heat sink blast path.
H02
Compressor lock
∗
Over-current detection after
compressor start-up
Stop
Displayed when
trouble is detected
1. Trouble of compressor (Lock, etc.): Replace compressor.
2. Wiring trouble of compressor (Open phase)
H03
Current detection circuit trouble
Stop
Displayed when
trouble is detected
1. Check outdoor P.C. board (MCC-1698).
(AC current detection circuit)
P05
Open phase of 3-phase power
supply
Stop
Displayed when
trouble is detected
1. Check open phase of 3-phase power supply.
2. Connection check between CN50 of MCC-1600 and
CN608 of MCC-1675.
P15
Detection of gas leak
∗
Discharge temp. sensor (TD),
Suction temp. sensor (TS) detected
temperature over specified temp.
Stop
Displayed when
trouble is detected
1. Check gas leak, recharge
2. Check full open of service valve.
3. Check PMV (Pulse Motor Valve).
4. Check broken pipe.
5. Check discharge temp. sensor (TD), suction temp.
sensor (TS).
P19
4-way valve inverse trouble
∗
After heating operation has started,
indoor heat exchanger temp. lowers
under the specified temp.
∗
After heating operation has started,
outdoor heat exchanger / suction
temp. rises over the specified temp.
Stop
Displayed when
trouble is detected
1. Check operation of 4-way valve.
2. Check outdoor heat exchanger (TE), suction temp.
sensor (TS).
3. Check indoor heat exchanger sensor (TC).
4. Check 4-way valve coil.
5. Check PMV (Pulse Motor Valve).
H01
Compressor break down
∗
Although operation has started,
operation frequency decreases and
operation stops.
Stop
Displayed when
trouble is detected
1. Check power supply voltage. (AC342 to 457V)
2. Overload operation of refrigerating cycle
