Servicing Tools - Hitachi RAF-25NH4 Service Manual

3. Servicing Tools

Changes in the Product and Components
〈
In order to prevent any other refirigerant from being charged, R410A model is provided with the outdoor
unit whose control valve has a different service port diameter (port size: 7/16 UNF 20 threads per inch
1/2 UNF 20 threads per inch).
→
In order to secure larger pressure resisting strength, flare expansion pipe dimensions and flare nut
dimensions have been changed.
New Tools for R410A
〈
New tools for R410A
Gauge manifold
Charge hose
Electronic balance for
refrigerant charging
Torque wrench
Flare tool (clutch type)
Gauge for projection
adjustment
Vacuum pump adapter
Gas leakage detector
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" require 1/2 UNF 20 threads per inch
corresponding to the charge hose's port size.
〉
〉
Applicable to
HCFC-22 Model
×
×
○
×
(nominal diam.
1/2, 5/8)
○
−
○
×
As pressure is high, it is impossible to measure by means of
conventional gauge. In order to prevent any other refrigerant
from being charged, each port diameter has been changed.
In order to increase pressure resistance, hose materials and
port size have been changed (to 1/2 UNF 20 threads per
inch). When purchasing a charge hose, be sure to confirm
the port size.
As 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.
The opposite side dimensions of flare nuts increase.
Incidentally, a common wrench is used for nominal diameters
1/4 and 3/8.
By increasing the clamp bar's receiving hole, strengh of spring
in the tool has been improved.
Used when performing flare processing by means of
conventional flare tool.
Connected to conventional vacuum pump.
Exclusive for HFC refrigerant.
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Changes