Mitsubishi Electric PUD-SWM60VAA Service Manual page 21

Symbol
COMP Compressor
H/P SW High pressure switch (63H)
REV/V Reversing (4-way) valve (21S4)
CHECK/V Charge plug
P-SENSOR Pressure sensor (63HS)
LEV-A Linear expansion valve -A
LEV-C Linear expansion valve -C
TH32 Suction temperature thermistor
TH3 Liquid temperature thermistor
TH4 Discharge temperature thermistor
TH6 2-phase pipe temperature thermistor
TH7 Ambient temperature thermistor
TH33 Comp. surface temperature thermistor For protection
HIC Heat Interchanger
REFRIGERANT COLLECTING (PUMP DOWN)
When relocating or disposing of the indoor/outdoor unit, pump down the system following the procedure below so that no refriger-
ant is released into the atmosphere.
1 Turn off the power supply (circuit breaker).
2 Connect the low pressure valve on the gauge manifold to the service port of the gas stop valve on the outdoor unit.
3 Close the liquid stop valve completely.
4 Supply power (circuit breaker).
• When power is supplied, make sure that "Centrally controlled" is not displayed on the remote controller. If "Centrally con-
trolled" is displayed, the refrigerant collecting (pump down) cannot be completed normally.
• Startup of the indoor-outdoor communication takes about 3 minutes after the power (circuit breaker) is turned on. Start the
pump-down operation 3 to 4 minutes after the power (circuit breaker) is turned on.
5 Perform the refrigerant collecting operation (cooling test run).
• Push the pump-down SWP switch (push-button type) on the control board of the outdoor unit. The compressor and ventilators
(indoor and outdoor units) start operating (refrigerant collecting operation begins). (LED1 and LED2 on the control board of
the outdoor unit are lit.)
• Only push the pump-down SWP switch if the unit is stopped. However, even if the unit is stopped and the pump-down SWP
switch is pushed less than 3 minutes after the compressor stops, the refrigerant collecting operation cannot be performed.
Wait until the compressor has been stopped for 3 minutes and then push the pump-down SWP switch again.
6 Fully close the gas stop valve on the gas pipe side of the outdoor unit when the pressure gauge on the gauge manifold shows
0.05 to 0 MPa [Gauge] (approx. 0.5 to 0 kgf/cm²) and quickly stop the outdoor unit.
• Because the unit automatically stops in about 3 minutes when the refrigerant collecting operation is completed (LED1 off,
LED2 lit), be sure to quickly close the gas stop valve. However, if LED1 is lit, LED2 is off, and the unit is stopped, open the
liquid stop valve completely, close the valve completely after 3 minutes or more have passed, and then repeat step 5. (Open
the gas stop valve completely.)
• If the refrigerant collecting operation has been completed normally (LED1 off, LED2 lit), the unit will remain stopped until the
power supply is turned off.
• Note that when the extension piping is very long with a large refrigerant amount, it may not be possible to perform a pump-
down operation. In this case, use refrigerant recovery equipment to collect all of the refrigerant in the system.
7 Turn off the power supply (circuit breaker), remove the gauge manifold, and then disconnect the refrigerant pipes.
Warning:
When pumping down the refrigerant, stop the compressor before disconnecting the refrigerant pipes.
• If the refrigerant pipes are disconnected while the compressor is operating and the stop valve is open, the pressure in
the refrigeration cycle could become extremely high if air is drawn in, causing the pipes to burst, personal injury, etc.
OCH756
Parts name
DC inverter scroll compressor (Mitsubishi Electric Corporation)
For protection (OFF: 4.14 MPa)
Change the refrigerant circuit (Heating) and for Defrosting
(H) High pressure/(L) Low pressure/For production test use
For calculation of the condensing temperature from high pressure
Heating: Primary LEV
For HIC
For LEV control
Heating: Evaporating temperature
For LEV control and for compressor protection
Outdoor 2-phase pipe temperature
For fan control and for compressor frequency control
For high heating capacity
Detail
21