Precautions in Servicing The Models with New-type Refrigerant PACD011001C2
620 Appendix
7. Precautions in Servicing The Models with New-type
Refrigerant
Compared to the conventional refrigerant R22, the brand-new refrigerant R407C is higher in pressure. The
refrigerant oil is also different in type. With this in mind, note that the piping work procedures as well as the
related tools and piping materials are partially different than ever before.
7.1 Tools Required
Some specific tools are required for servicing the refrigerant line of the new-type refrigerant models. Select
the right tools referring to the table below.
Typical tools and materials for piping works and their interchangeability
Refrigerant Conventional type New type
R22 (single) R407C (mixed)
Refrigerant oil Mineral oil (Suniso) Synthetic oil (ether)
Condensation pressure 1.84MPa 2.01MPa
Name Work process and application Interchangeability with conventional tools and materials
Pipe cutter Refrigerant piping work Cutting pipes Interchangeable.
Flaring tool Flaring pipes
Refrigerant oil Applying on flared spots Specified ether oil, ester oil, alkyl benzene oil or their
mixture to be used.
Torque wrench
Connecting flare nut
Interchangeable.
Pipe expander Expanding pipes at
connections
Pipe bender Bending pipes
Nitrogen Air-tightness test Inhibiting oxidation in pipes
Welder Brazing pipes
Gauge manifold Air-tightness test through
refrigerant recharging
Vacuum refrigerant
charging and running test
Specific tools required for boosting the pressure and
preventing impurities from coming in.
Charging hose
Vacuum pump Vacuum drying Interchangeable.
(Adapter to be connected to keep the oil from flowing back
to the unit during pump shut-down. Pump with anti-backflow
function also available.)
Charging cylinder Refrigerant recharging Conventional cylinder not allowed because of different
refrigerant properties. (Need to weigh with the scale.)
Refrigerant charging
scale
Interchangeable.
Gas leak detector Gas leak test Specific detector needed. (R134a-compatible detector
allowed.)
To Next Page
Loading...
