Airwell Multi Split DUO 50 DCI, Service Manual

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APPENDIX A
SM DLF 1-A.1 GB
Installation/Service Tooling for R410A Changes
Gauge manifold As the working pressure is high, it is impossible
to measure the working pressure using
conventional gauges. In order to prevent any
other refrigerant from being charged, the port
diameters have been changed.
Charge
hose In order to increase pressure resisting strength,
hose materials and port sizes have been
changed (to 1/2 UNF 20 threads per inch).
When purchasing a charge hose, be sure to
confirm the port size.
Electronic scale for
refrigerant charging As working pressure is high and gasification
speed is fast, it is difficult to read the indicated
value by means of charging cylinder, as air
bubbles occur.
Torque wrench (nominal
dia. 1/2, 5/8) The size of opposing flare nuts has been
increased. Incidentally, a common wrench is
used for nominal diameters 1/4 and 3/8.
Flare tool (clutch type) By increasing the clamp bar's receiving hole
size, strength of spring in the tool has been
improved.
Gauge for projection adjustment Used when flare is made by conventional flare
tool.
Vacuum pump adapter & check valve Connected to a conventional vacuum pump. It
is necessary to use an adapter to prevent
vacuum pump oil from flowing back into the
charge hose. The charge hose connecting part
has two ports - one for conventional refrigerant
(7/16 UNF 20 threads per inch) and one for
R410A. If the vacuum pump oil (mineral) mixes
with R410A a sludge may occur and damage
the equipment.
Gas leakage detector Exclusive for HFC refrigerant.
Incidentally, the "refrigerant cylinder" comes with the refrigerant designation (R410A) and
protector coating in the U.S's ARI specified rose color (ARI color code: PMS 507). Also,
the "charge port and packing for refrigerant cylinder" requires 1/2 UNF 20 threads per inch
corresponding to the charge hose's port size.