Temperature change when condensers in off cycle. Detected at outdoor. Likely causes: PMV passing within condenser Discharge & suction pressure transducer error (PS & Pd characteristics) Interface PCB faulty

Sending error of local remote controller. Detected by remote controller. Likely causes: Faulty remote controller Cable / wiring problem

High side pressure sensor fault. Detected at outdoor. (Replace Pd pressure transducer)

This points towards a reverse change in temperature, detected by indoor evaporator sensor (TC). Likely causes: 4 way valve. 4 way reversing valve energised for heating operation. Faulty TC sensor.

Low pressure transducer error or misreading fault. Detected at outdoor. Likely causes: Incorrect characteristics of suction pressure transducer (PS) Interface PCB faulty

Oil sensor fault. Detected at outdoor. Likely causes: TK2 sensor condition - sensor value 20°C=63k Ohms Outdoor PCB faulty

Command receiving error. Detected on Central Controller. Likely causes: Power loss at indoor unit group Network cable condition

Condenser coil sensor (TE) fault. Detected indoors. Likely causes: TE/TE1 sensor condition / fault - sensor value 20°C=12.5k Ohms. Outdoor PCB fault.

Communication error between indoor unit and central remote controller. Detected indoors. Likely causes: Indoor network adapter fault Central remote controller fault

High temperature oil alarm. Detected at outdoor. Likely causes: TK1 sensor condition - sensor value 20°C=63k Ohms Interface PCB faulty High ambient running conditions >43°c

Outdoor unit address incorrect. Detected at outdoor. Likely causes: Multiple modularised condenser having SW 9 ON Interface PCB failure

External input activation, refrigerant leak detection system (Call Toshiba's technical helpline for further details 0870 843 0333)

Indoor unit automatic addressing failure. Detected at outdoor. Likely causes: Indoor PCB configuration error Indoor PCB faulty

Phase rotation incorrect. Detected at outdoor. Likely causes: Abnormal phase order Missing phase to outdoor unit

High compressor discharge temperature. Detected at outdoor by TD1. Likely causes: Low refrigerant Poor refrigerant flow Airflows TD2 sensor faulty - sensor value 20°C=63k Ohms

2 Pipe VRF & Split A/C equipment High Pressure switch activation 425psi-29bar. 3 Pipe VRF equipment, interrogate condenser PCB for additional fault code. Detected at outdoor. Likely causes: Split A/C equipment faulty H.P. switch, restriction in refrigerant flow, fan motor failure, poor airflows. VRF equipment, set condenser interface PCB switches as follows SW1 @ position 2 & SW2 @ position 0 (see sub codes Er21 or ErAd)

Outdoor unit automatic address failure. Detected at outdoor. Likely cause: Interface PCB faulty

Compressor suction sensor fault. Detected at outdoor. Likely causes: TS1/ThS sensor condition - sensor value 20°C=12.5k Ohms Interface PCB faulty

On split A/C equipment it signifies an indoor to outdoor communication failure. On VRF equipment it could also be attributed to communication breakdown between condenser PCB's. Likely causes: - Indoor PCB. - Condenser PCB. - Interconnecting Wiring. - Fault with the transformer used to power condenser PCB.

Indoor group follower error. Detected at central controller (interrogate local controller by pressing check for additional fault codes)

Master condenser setup alarm. Detected at outdoor. Likely causes: Multiple inverter outdoor units connected Faulty interface PCB

High compressor discharge temperature. Detected at outdoor by TD2. Likely causes: Refrigerant shortage Poor refrigerant flow Poor airflows TD2 sensor condition - sensor value 20°C=63k Ohms

Oil temperature alarm. Detected at outdoor. Likely causes: TK1 sensor location or condition - sensor value 20°C=63k Ohms Outdoor PCB faulty

Return air sensor fault. Detected indoors. Likely causes: TA sensor condition - sensor value 20°C=12.5k Ohms. Indoor PCB faulty.

No oil flow detected. Detected at outdoor. Likely causes: TK1, TK2 & TK3 sensor location or condition - sensor value 20°C=63k Ohms Interface PCB faulty Blockage within SV3C

Outdoor unit quantity fallen (loss of communication between condensers). Detected at outdoor. Likely causes: Power interruption BUS communication Cable / wiring problem between condening units

Oil temperature alarm. Detected at outdoor. Likely causes: TK2 sensor location or condition - sensor value 20°C=63k Ohms Outdoor PCB faulty

Pressure transducer error. Detected at outdoor. Likely causes: Abnormal running pressures Abnormal PS / Pd characteristics Interface PCB faulty

Low oil detection. Detected at outdoor. Likely causes: TK1, TK2 & TK3 sensor condition - sensor value 20°C=63k Ohms Interface PCB faulty Refrigerant shortage

Communication failure between indoor and outdoor units. Detected indoors. Likely causes: Split A/C Indoor PCB fault Outdoor PCB fault Interconnecting cable condition Compressor klixon open circuit. VRF system Power loss at condenser U1/U2 network cable issue

Compressor discharge sensor fault. Detected at outdoor. Likely causes: TD1/ThD1 sensor condition - sensor value 20°C=63k Ohms Interface PCB faulty

Duplicated zone address. Likely causes: Incorrectly assigned central control addresses.

Communication error between indoor unit and remote controller. Detected by remote controller. Likely causes: Indoor PCB faulty Remote controller faulty Incorrect switch position on rear of remote controller, all switches normally down Cable / wiring problem

Liquid or Compressor discharge sensor fault. Likely causes TL,TD sensor condition / faulty - TL sensor value 20°C=12.5k Ohms, TD sensor value 20°C=63k Ohms PCB faulty.

Oil sensor fault. Detected at outdoor. Likely causes: TK1 sensor condition - sensor value 20°C=63k Ohms Outdoor PCB faulty

Outdoor error. Detected indoors (Interrogate condenser units for additional faults)

Abnormal overheat of heat-sink. Detected at outdoor. Likely causes: Clogged heat-sink fins Poorly secured PCB (Has heat sink paste been used) Faulty IPDU board

Multi-Controller box Th(B) sensor fault. Likely causes: TH(B) sensor or M/C box PCB sensor value 20°C=12.5k Ohms

Pressure sensor fault. Detected indoors. Likely causes: Evaporator pressure sensor unplugged Pressure sensor open circuit

Indoor coil sensor fault. Detected indoors. Likely causes: TC1 sensor condition - sensor value 20°C=12.5k Ohms. Indoor PCB faulty.

No communication from indoor to remote controller. Detected by hard-wired remote controller. Likely causes: Faulty indoor PCB. Remote controller faulty. Cable damage.

Low pressure trip. Detected outdoor by PS transducer. Likely causes: Suction pressure transducer condition (PS) Interface PCB fault Restriction in refrigerant flow Refrigerant shortage

IPDU PCB overheat (Inverter board). Detected at outdoor. Likely causes: Clogged heat-sink fins Poorly secured PCB (Has heat sink paste been used) Faulty IPDU PCB

High compressor discharge temperature @ low inverter speed. Detected at outdoor. Likely causes: TD1 sensor condition - value 20°C=63k Ohms Insufficient refrigerant sensor

Frost conditions detected / No temperature change. Detected indoors by evaporator sensor (TC). Likely causes: Poor airflow. Refrigerant Shortage. Overheating compressor.

External input activation, refrigerant leak detection system (Call Toshiba's technical helpline for further details 0870 843 0333)

Multi-Control box does not recognise condenser capacity. Likely causes: Interconnecting cable damage. Outdoor PCB fault.

Multi-Controller box Th(D) sensor fault. Likely causes: TH(D) sensor or M/C box PCB sensor value 20°C=12.5k Ohms

Communication failure on P&Q network (indoor/outdoor communication). Detected indoors & outdoors. Likely causes: Network cable condition. PCB failure, indoor or outdoor.

Inverter compressor PCB short circuit. Detected at outdoor. Likely causes: Blown fuses supplying inverter pack. Faulty IPDU (inverter board) or component within inverter pack. Electrical fault on inverter compressor.

Central control communication error. Detected at central controller & indoors. Likely causes: Indoor power failure. Central controller address error. Cable damage.

Multi-Controller box Th(X) sensor fault. Likely causes: TH(X) sensor or M/C box PCB sensor value 20°C=12.5k Ohms

Multi-Controller box error. Detected indoors (Interrogate Multi-Controller box for additional faults by setting display switch @ position 1)

Outdoor units quantity too high. Detected at outdoor. Likely cause: Too many condensers connected

Phase missing / Phase Rotation. Detected at outdoor. Likely causes: Abnormal power supply.

Multi-Controller box Th(A) sensor fault. Likely causes: TH(A) sensor or M/C box PCB sensor value 20°C=12.5k Ohms

Multi-Controller box Th(C) sensor fault. Likely causes: TH(C) sensor or M/C box PCB sensor value 20°C=12.5k Ohms

No temperature change in evaporator. Detected by indoor evaporator sensor TC1. Likely causes: Miss-wiring Restriction in refrigerant flow Refrigerant shortage

Indoor float switch open circuit as result of high condensation levels within drip tray. Detected indoors. Likely causes: Faulty float switch. Faulty lift pump. Drain blocked.

EEPROM Failure on PCB. Detected indoors (replace indoor PCB)

High compressor discharge temperature. Detected at outdoor. Likely causes: Low refrigerant charge Poor refrigerant flow, blockage Poor airflows TD sensor condition - sensor value 20°C=63k Ohms

Indoor fan trouble. Detected indoors. Likely causes: Fan motor. Indoor PCB. On a cassette, packing foam has not been removed.

Fault within follower condenser. Detected at outdoor. (retrieve additional fault code information from follower condensers)

Command sending error. Detected on Central Controller. Likely causes: Power loss at indoor unit group Network cable condition

High Inverter AC current. Detected at outdoor. Likely causes: Imbalance in compressor voltage draw Excessive amps drawn by inverter compressor

Communication failure between indoor and outdoor units. Detected at outdoor. Likely causes Interconnecting cable problem Outdoor PCB switch position SW30 bit 1 & 2 must be placed in ON position for test

High Inverter DC current. Detected at outdoor. Likely causes: Imbalance in compressor voltage Excessive amps drawn by inverter compressor

Excessive high pressure. Detected at outdoor. Likely causes: Abnormal characteristics of Pd transducer. Refrigerant restriction/blockage

Condenser PCB faulty (Replace main PCB)

Insufficient temperature change on evaporator. Detected indoors. Likely causes: Miss-wiring Restriction in refrigerant flow Refrigerant shortage TC1,TC2 & TA sensor condition - sensor value 20°C=12.5k Ohms

Decrease in quantity of indoor units. Detected indoors. Likely causes: Power loss at indoor unit Indoor PCB faulty A&B controller wiring problem

Abnormal current detection on inverter compressor. Detected at outdoor. Possible causes: IPDU PCB (Inverter board) faulty. Compressor faulty.

Compressor discharge sensor fault. Detected at outdoor. Likely causes: TD2/ThD2 sensor condition - sensor value 20°C=63k Ohms Interface PCB faulty

High compressor suction temperature > 40°C. Detected at outdoor. Likely causes: Severe gas shortage TS sensor condition - sensor value 20°C=12.5k Ohms Interface PCB faulty

Indoor unit count too high. Detected at outdoor. Likely causes: Indoor capacity vs. outdoor capacity Incorrect. Too many indoor units connected.

Indoor capacity to high. Likely causes: Loss of combination within group of modularised condensers.

Coil sensor fault. Detected indoors. Likely causes: TC sensor condition - Sensor value 20°c=12.5k Ohms Indoor PCB fault

Indoor coil sensor fault. Detected indoors. Likely causes: TC2 sensor condition - sensor value 20°C=12.5k Ohms. Indoor PCB faulty.

Oil sensor fault. Detected at outdoor. Likely causes: TK3 sensor condition - sensor value 20°C=63k Ohms Outdoor PCB faulty