Panasonic CU-YL28HBE5, Руководство по обслуживанию

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2. Installation work
a. Brazing work
Brazing work needs replacing air inside pipe with nitrogen gas in order to prevent oxidization scale from occurring. This is
called nitrogen replacement, and one of very important work in brazing refrigerant piping. (Oxidation preventive is not
possible to use)
b. Prevention measure for refrigerant piping
Prevention measure for refrigerant piping is very important work to prevent water-dust-rubbish from getting in.
All piping terminals needs sealing such as shown below.
• How to pinch
Close terminal part of piping with pliers and seal the
gap with brazing.
• How to tape
Seal terminal part of piping with vinyl tape.
3. Vacuum pumping
The purpose of vacuum pumping work is to remove and dry air inside the piping or nitrogen at air tightness test.
Perform the work carefully.
Vacuum pump capacity 60 l/min or more
4. Refrigerant filling
Refrigerant filling must be done in the state of liquid
refrigerant.
If this is done in gas refrigerant, the balance of refrigerant
composition will collapse and damage the operation.
For the use of a gas cylinder without siphon inside, turn it
upside down and use it.
(We recommend manifold with sight glass.)
Place Period of work Method of seal
Outside More than 1 month Pinch
Less than 1 month Pinch or taping
Inside Not specified
Use the vacuum pump with the backflow prevention mechanism to prevent backflow of oil.
Vacuuming time 60 minutes or more