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2. SERVICE FOR REFRIGERANT LINES
[a] SERVICE INFORMATION
1)
Allowable Compressor Opening Time and Prevention of Lubricant Mixture
[R290]
The compressor must not be opened more than 30 minutes in replacement or service.
Do not mix lubricants of different compressors even if both are charged with the same
refrigerant, except when they use the same lubricant.
2) Treatment for Refrigerant
Leak [R290]
If a refrigerant leak occurs in the low side of an ice maker, air may be drawn in. Even
if the low side pressure is higher than the atmospheric pressure in normal operation, a
continuous refrigerant leak will eventually lower the low side pressure below the
atmospheric pressure and will cause air suction. Air contains a large amount of moisture,
and ester oil easily absorbs a lot of moisture. If an ice maker charged with R290 has
possibly drawn in air, the drier must be replaced. Be sure to use a drier designed for
R290.
3)
Handling of Handy Flux [R290]
Repair of the refrigerant circuit needs brazing. It is no problem to use the same handy
flux that has been used for the current refrigerants. However, its entrance into the
refrigerant circuit should be avoided as much as possible.
4)
Oil for Processing of Copper Tubing [R290]
When processing the copper tubing for service, wipe off oil, if any used, by using alcohol
or the like. Do not use too much oil or let it into the tubing, as wax contained in the oil
will clog the capillary tubing.
5)
Service Parts for R290
Some parts used for refrigerants other than R290 are similar to those for R290. But
never use any parts unless they are specified for R290 because their endurance
against the refrigerant has not been evaluated. Also, for R290, do not use any parts that
have been used for other refrigerants. Otherwise, wax and chlorine remaining on the
parts may adversely affect R290.
Only trained service engineer can service the R290 refrigeration unit.
