Concealed Duct High Static Pressure
Installation Manual
Concealed Duct High Static Pressure | Installation Manual |
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Tightening connection
CAUTION
Do not apply excessive torque. Otherwise, the nut may crack depending on the conditions.
| (Unit: N•m) |
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Outer dia. of copper pipe | Tightening torque |
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12.7 mm (dia.) | 50 to 62 (5.0 to 6.2 kgf•m) |
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uTightening torque of flare pipe connections
Pressure of R410A is higher than that of R22. (Approx. 1.6 times)
Therefore, using a torque wrench, tighten the flare pipe connecting sections which connect the indoor and outdoor units of the specified tightening torque.
Incorrect connections may cause not only a gas leak, but also a trouble of the refrigeration cycle.
Align the centres of the connecting pipes and tighten the flare nut as far as possible with your fingers.
Then tighten the nut with a spanner and torque wrench as shown in the figure.
Half union | Flare nut |
Externally | Internally |
threaded side | threaded side |
Use a wrench to secure. | Use a torque wrench to tighten. |
REQUIREMENT
Tightening with an excessive torque may crack the nut depending on installation conditions.
Tighten the nut within the specified tightening torque.
nGas side refrigerant pipe connection
•Turn up the pipe heat insulator to the unit side.
•Wrap the pipe with wet cloth.
Turn up pipe heat insulator
Wet cloth
Remove the all brazed part.
•Remove the cup on the gas side piping by using a brazing machine.
CAUTION
Do not burn the pipe heat insulator.
Remove the cap.
Attached joint part
Connection pipe Locally procured Ø28.6 mm
•Braze the attached joint part to the gas side piping and braze the connection piping to the joint part.
Brazing
Braze all around
Brazing
•Turn back the pipe heat insulator and tie up with a banding band.
Tie up with a banding band.
Piping with outdoor unit
•For details of installation, refer to the Installation Manual of the outdoor unit.
nEvacuation
Using a vacuum pump, perform vacuuming from the charge port of valve of the outdoor unit.
For details, follow to the Installation Manual attached to the outdoor unit.
•Never use the refrigerant sealed in the outdoor unit for evacuation.
REQUIREMENT
For the tools such as charge hose, etc., use those manufactured exclusively for R410A.
Refrigerant amount to be added
For addition of the refrigerant, add refrigerant “R410A” referring to the attached Installation Manual of outdoor unit.
Be sure to use a scale to charge the refrigerant of specified amount.
REQUIREMENT
•Charging an excessive or too little amount of refrigerant causes a trouble of the compressor.
Be sure to charge the refrigerant of specified amount.
•A personnel who charged the refrigerant should write down the pipe length and the added refrigerant amount in the nameplate attached to the service panel of the outdoor unit.
It is necessary to fix the compressor and refrigeration cycle malfunction.
Open the valve fully
Open the valve of the outdoor unit fully.
A
For details, refer to the Installation Manual attached to the outdoor unit.
Gas leak check
Check with a leak detector or soap water whether gas leaks or not, from the pipe connecting section or cap of the valve.
REQUIREMENT
Use a leak detector manufactured exclusively for HFC refrigerant (R410A, R134a, etc.).
Heat insulation process
Apply heat insulation for the pipes separately at liquid side and gas side.
For the heat insulation to the pipes at gas side, be sure to use the material with
Using the attached heat insulation material, apply the heat insulation to the pipe connecting section of the indoor unit securely without gap.
REQUIREMENT
•Apply the heat insulation to the pipe connecting section of the indoor unit securely up to the root without exposure of the pipe.
(The pipe exposed to the outside causes water leak.)
•Wrap heat insulator with its slits facing up (ceiling side).
Indoor unit
Union
| Heat insulator |
Heat insulation | Flare nut of the pipe |
(Accessory) |
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