Panasonic OCU-CR1000VF8A, Service Manual

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Gas Leak Repair Procedure
1. Gas leak position identification
1) When using a liquid type leak detector
Identify the position where oil is leaking.
Find gas leaks by applying the liquid type leak detector and checking for foaming.
2) When using a leak detector
Identify the position where oil is leaking.
Detect gas leaks by bringing the leak detector probe near the identified position.
Note: Use caution not to blow air during the detection process. Detector reacts to blown air.
2. Releasing refrigerant
Release refrigerant in accordance
with “Refrigerant Releasing Procedure".
3. Brazing repair operation
1) Prepare for brazing operation.
You will need the following tools during brazing operation:
- Brazing burner
- Phosphor copper solder
If silver brazing solder is to be used, do not use any flux containing chlorine.
- Shield plate, heat insulation plate, wet waste cloth
- Blow and replacement nitrogen
2) Carry out brazing operation.
Since the copper pipes used with the CO
2
refrigeration unit have a thicker wall than the
HFC refrigeration unit, make sure that the melted brazing material is fully wetting the target
position.
Notes: 1. Maintain a flow of oxygen-free nitrogen through the brazing position at a very low
pressure during brazing. Nitrogen displaces the air and prevents the formation of
copper oxides in the brazing position.
2. During brazing, make sure that there is no refrigeration oil residue on the surface.
4. Airtight test
Carry out the airtight test in accordance with "Airtight Test Procedure ".
5. Evacuation
Carry out the evacuation in accordance with "Vacuum Pump Attachment and Evacuation
Procedure".
6. Refrigerant Charging
Charge the refrigeration unit with refrigerant in accordance with "Refrigerant Charging
Procedure".
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