Toshiba A90-0132, Service Manual

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14
Troubleshooting
Description of functional parts
Functional part Functional outline
Solenoid valve 1. SV3A 1) Accumulates oil from the compressor to the oil tank when the valve is shut.
(CN312) 2) Supplies the gathered oil to the balancing pipe during ON time when pressure is applied to inside of the oil tank.
3) Supplies oil directly to the balancing pipe when the valve is open and pressure is applied.
4) Reduces pressure after pressure has been applied to inside of the oil tank.
2. SV3B 1) Returns oil supplied in the balancing pipe to the compressor.
(CN313)
3. SV3C 1) Applies pressure to inside the oil tank during ON time.
(CN314) 2) Detects oil level with temp. system.
4. SV2 (Hot gas bypass) (Compressor case bypass)
(CN312) 1) Low pressure release valve. 1) Maintains oil viscosity.
(To protect reduction of low pressure)
2) Protects liquid refrigerant gathering in accumulator.
3) Gas balancing in STOP time.
5. SV41/SV42 (Activation compensating valve for fixed-speed compressor)
(CN311) 1) For activation of gas balance.
2) Deflates gas in discharge pipe. (Protects liquid stagnation in discharge pipe.)
Check valve Check valve 1) Protects counter pressure when the inverter compressor is operating and the fixed speed compressor stops.
for discharge 2) Decreases activation load when fixed-speed compressor is activated.
(Shared function with SV41/SV42 valve)
Pulse 1. PMVB (Cooling bypass) (Connector CN302 Red)
motor valve 1) Liquid bypass proportional control function for releasing discharge temperature
2) Releases low pressure.
Oil separator 1) Early protection of oil level down (Decreases flow-out of discharge oil to cycle)
Temperature 1. TD1(CN502) (TD1: Connector: Red, TD2: Connector: White)
sensor TD2(CN503) 1) Used to protect discharge temperature from the compressor.
2) Used to control cooling bypass for releasing discharge temperature.
2. TS1(CN504) (Connector: White)
1) Used to control cooling bypass for releasing discharge temperature.
3. TK1(CN516) (TK1: Connector: Black, TK2: Connector: Blue, TK3: Connector: Green)
TK2(CN515) 1) Used to detect oil level judgment. (TK1, TK2)
TK3(CN507) 2) Used to detect dilution status of oil. (TK3)
4. TE1(CN505) Used for fan control and to detect heat exchanger defrost requirement.
Pressure 1. High pressure (Connector: Red)
sensor sensor 1) Used to detect high pressure, and compressor capacity.
(CN501) 2) In cooling operation, it is used to detect high pressure, and control the fan in cooling low ambient conditions.
2. Low pressure (Connector: Blue)
sensor 1) In cooling operation, it is used to detect low pressure, and control the capacity of the compressor.
(CN500) 2) Super-heat is controlled by monitoring low pressure during heating operation.
Balancing pipe 1) Oil supply path for balancing oil of each outdoor unit.
2) Low pressure bypass function between outdoor units, which recovers the liquid refrigerant stagnated in any stand-by
outdoor unit.
3) Low pressure balancing pipe function to secure pressure difference when check valve of every outdoor unit aligned on a
circuit in parallel are inverted.