| Unit : ft•lbs (N•m) |
Outer dia. of copper pipe | Tightening torque |
|
|
1/4" (6.4 mm) | 10 - 13 (14 - 18) |
|
|
3/8" (9.5 mm) | 24 - 31 (33 - 42) |
|
|
1/2" (12.7 mm) | 37 - 46 (50 - 62) |
|
|
5/8" (15.9 mm) | 46 - 57 (63 - 77) |
|
|
▼Tightening torque of flare pipe connections
Pressure of R410A is higher than that of R22.
Installation Manual
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.
(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.
Flare at indoor 
unit side
Flare at 
outdoor unit side
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 |
Align the centers 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.
Piping with outdoor unit
•Shape of valve differs according to the outdoor unit. For details of installation, refer to the Installation Manual of the outdoor unit.
Evacuation
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 air purge.
service panel of the outdoor unit. It is necessary to |
troubleshoot the compressor and refrigeration cycle |
malfunction. |
Open the valve fully
Open the valve of the outdoor unit fully. A 4 mm hexagonal wrench is required for opening the valve. 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.).
Thermal insulation process
Apply thermal insulation for the pipes separately at liquid side and gas side.
For the thermal insulation to the pipes at gas side, be sure to use the material with
Using the attached thermal insulation material, apply the thermal insulation to the pipe connecting section of the indoor unit securely without gap.
REQUIREMENT
•Apply the thermal insulation to the pipe connecting section of the indoor unit securely up to the root
– 17 – |
