Panasonic U-4LE1E5, Service Manual, Page: 45 / 133

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Mini VRF SYSTEM
Outdoor Unit Repair Procedures
7. Compressor
8. High Pressure Sensor
(1)
(2)
(3)
(1)
8. High Pressure Sensor
The high pressure sensor connection port on the outdoor unit
includes a Schrader-type, push-to-release valve. It is not necessary
to recover the refrigerant when removing and installing the sensor.
8-1. Removing the High Pressure Sensor
Refer to “1. Removing Panels” and remove the front panel.
Disconnect the high pressure sensor connector (3P - BLK) from
terminal CN-HPS on the outdoor unit control PCB of the outdoor unit
where the high pressure sensor will be removed.
Use 2 adjustable wrenches in combination to remove the high
pressure sensor.
The high pressure sensor connection port on
the outdoor unit includes a Schrader-type
valve. When removing the high pressure
sensor, internal pressure will be applied from
the refrigerant in the outdoor unit.
8-2. Installing the High Pressure Sensor
Use 2 adjustable wrenches in combination to install the high
pressure sensor.
CAUTION
Installation
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
Prepare for installation.
• Remove the rubber stopper and tube cap (welded) from the new compressor.
Install the crankcase heater onto the compressor.
Place the cushioning rubber in the designated positions on the compressor.
(There are 3 pieces for an inverter compressor.)
Set the new compressor into the unit.
Shape the tubes and insert them at the 2 welding locations.
Use nitrogen to replace the air inside the compressor. Perform brazing at all parts.
Increase the pressure to the nitrogen airtightness test pressure of 3.80 MPa. Check that no leakage occurs.
Re-install all components that were removed. Re-install the electrical component box in the original position
as it was before.
After the airtightness test is completed, apply vacuum until a pressure of –101 kPa (–775 mm Hg, 5 Torr) or
less is reached at the indoor and outdoor units and in the tubing.
After applying vacuum, charge with refrigerant.
For the refrigerant charging methods, refer to “Installation
Instructions.”
Charge with the total of the “refrigerant amount at time of
shipment” plus the “additional charge amount.” (Listed on
the nameplate and description label.)
• Be sure to perform refrigerant charge using liquid refrigerant.
Never use any refrigerant other than R410A.
Connection port
(Schrader-type)
High pressure
sensor
Fig. 2-12
Front side
SM830195-01̲Mini VRF SYS.indb 17 SM830195-01̲Mini VRF SYS.indb 17 2011/12/20 16:31:18 2011/12/20 16:31:18