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Design of W-3WAY ECO-i SYSTEM Unit Specifi cations
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4. Installation Instructions
Precautions for brazing
Be sure to replace the air inside the tube with nitrogen to prevent oxide fi lm from forming during the brazing process.
Be sure to use a damp cloth or other means to cool the valve unit during brazing.
CAUTION
1. Be sure to use nitrogen. (Oxygen, CO
2
, and CFC must not be used.)
2. Use a pressure-reducing valve on the nitrogen tank.
3. Do not use agents intended to prevent the formation of oxide film. They will adversely affect the
refrigeration oil, and may cause equipment failure.
4. The balance tube is not used if only 1 outdoor unit is installed.
Use the unit in the same conditions as when it was shipped from the factory.
Tighten each cap as specifi ed below.
Tightening torque for each cap
Service port cap
(width 19/32")
60 – 100 in.lbs (70 – 120 kgf · cm)
Valve cap
(width 55/64")
170 – 220 in.lbs (200 – 250 kgf · cm)
Flare nut
(valve dia. ø3/8")
300 – 360 in.lbs (340 – 420 kgf · cm)
Brazing locations
Field-supply tube
Taping
Remote valve
Nitrogen
Pressure-reducing valve (regulator)
Work method
Use two monkey wrenches, as shown in the figure,
when removing the liquid tube valve flare nut.
1. Do not apply a wrench to the valve cap when removing or
installing the flare nuts. Doing so may damage the valve.
Do not apply a monkey wrench
to the hexagonal part.
Do not use two monkey wrenches when
removing or installing the balance tube
flare nut. In particular, do not apply a
monkey wrench to the hexagonal part at
the top of the valve.
(If force is applied to this part,
gas leakage will occur.)
2. If the valve cap is left off for a long period of time, refrigerant
leakage will occur. Therefore, do not leave the valve cap off.
3. Applying refrigerant oil to the flare surface can be effective in
preventing gas leakage, however be sure to use a refrigerant
oil which is suitable for the refrigerant that is used in the system.
(This unit utilizes R410A refrigerant, and the refrigerant oil is
ether oil (synthetic oil). However, hub oil (synthetic oil) can also
be used.)
Valve cap
Flare nut
Service port cap
TD831139̲Sec2̲p31-44.indd 39
TD831139̲Sec2̲p31-44.indd 39
2008/04/17 15:33:21
2008/04/17 15:33:21