Connection System; Sealing Test; Vacuum Process; Additional Charging - Fujitsu WOYK150LJL Installation Manual

Air to water heat pump outdoor unit
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5.4.3. Handling precautions for the valves
• Mounted part of Blank cap is sealed for protection.
• Fasten blank cap tightly after opening valves.
Blank cap [mm (in.)]
6.35 (1/4)
9.52 (3/8)
12.70 (1/2)
15.88 (5/8)
19.05 (3/4)
Operating the valves
• Use a hexagon wrench (size 3/16 in (4 mm)).
Opening:
(1) Insert the hexagon wrench into the
valve shaft, and turn it counterclock-
wise.
(2) Stop turning when the valve shaft can
no longer be turned. (Open position)
Closing:
(1) Insert the hexagon wrench into the
valve shaft, and turn it clockwise.
(2) Stop turning when the valve shaft can
no longer be turned. (Closed position)

5.5. Connection System

Fig. A Connection system
Outdoor unit
Indoor unit
Fig. B
Valve
Open
Close
Cap
Table. A
Pipe
Spindle
6.0 to 7.0 N·m
Liquid valve
(60 to 70 kgf·cm)
6.0 to 7.0 N·m
Gas valve
(60 to 70 kgf·cm)

5.6. Sealing test

Use only nitrogen gas.
Never use refrigerant gas, oxygen, infl ammable gas, or poisonous gas to pressurize
the system.
(If oxygen is used, there is the danger of an explosion.)
Do not apply shock during sealing test.
It can rupture the pipes and cause serious injury.
Do not turn on the power unless all operations are complete.
En-7
Table A
Tightening torque [N·m (kgf·cm)]
20 to 25 (200 to 250)
20 to 25 (200 to 250)
28 to 32 (280 to 320)
30 to 35 (300 to 350)
35 to 40 (350 to 400)
Opening
direction
Opening
Hexagon wrench
direction
Liquid
Gas pipe
pipe
Pressure regulating valve
Pressure gauge
Nitrogen
R410A
Vacuum
Scale
pump
Charging cap
Spindle
Open
Close
Cap
Charging cap
20.0 to 25.0 N·m
10.0 to 12.0 N·m
(200 to 250 kgf·cm)
(100 to 120 kgf·cm)
30.0 to 35.0 N·m
10.0 to 12.0 N·m
(300 to 350 kgf·cm)
(100 to 120 kgf·cm)
CAUTION
Do not block the walls and the ceiling until the sealing test and the charging of the
refrigerant gas have been completed.
After connecting the pipes, perform a sealing test.
(1) Recheck that the spindle of the 3-way valve are closed before performing a sealing
test. (Refer to "5.5. Connecction System", Fig. B)
(2) Pressurize nitrogen gas to 4.2 MPa to perform the sealing test.
(3) Add nitrogen gas to both the liquid pipes and the gas pipes.
(4) Check all fl are connection areas and welded areas. Then, check that the pressure
has not decreased.
(5) Compare the pressures after pressurizing and letting it stand for 24 hours, and
check that the pressure has not decreased.
* When the outdoor temperature changes 5 °C, the test pressure changes 0.05 MPa.
If the pressure has dropped, the pipe joints may be leaking.
(6) If a leakage is found, immediately repair it and perform the sealing test again.
* Decrease the pressure of nitrogen gas before blazing.
(7) After completing the sealing test, release the nitrogen gas from both valves.
Seal
Release the nitrogen gas slowly.
(blank cap
installation
portion)

5.7. Vacuum process

Do not turn on the power unless all operations are complete.
If the system is not evacuated suffi ciently, its performance will drop.
Be sure to evacuate the refrigerant system using a vacuum pump.
The refrigerant pressure may sometimes not rise when a closed valve is opened after
the system is evacuated using a vacuum pump. This is caused by the closure of the
refrigerant system of the outdoor unit by the electronic expansion valve. This will not
affect the operation of the unit.
Use a clean gauge manifold and charging hose that were designed specifi cally for use
with R410A. Using the same vacuum equipment for different refrigerants may damage
the vacuum pump or the unit.
Do not purge the air with refrigerants, but use a vacuum pump to evacuate the system.
If moisture might enter the piping, follow below.
(I.e., if doing work during the rainy season, if the actual work takes long enough that
condensation may form on the inside of the pipes, if rain might enter the pipes during
work, etc.)
• After operating the vacuum pump for two hours, pressurize to 0.05 MPa (i.e., vacuum
breakdown) with nitrogen gas, then depressurize down to -100.7kPa (-755mmHg) for
an hour using the vacuum pump (vacuum process).
• If the pressure does not reach -100.7kPa (-755mmHg) even after depressurizing for at
least two hours, repeat the vacuum breakdown - vacuum process.
After vacuum process, maintain the vacuum for an hour and make sure the pressure
does not rise by monitoring with a vacuum gauge.
Evacuation procedure
(1) Remove the caps of the gas pipe and liquid pipe and check that the valves are
closed.
(2) Remove the charging cap.
Hexagon
(3) Connect a vacuum pump and a pressure gauge to a charging hose and connect it
wrench
to the charging port.
(4) Activate the vacuum pump and vacuum the indoor unit and connection piping until
the pressure gauge becomes -100.7kPa (-755mmHg).
Evacuate from both the gas pipe and the liquid pipe.
(5) Continue evacuating the system for 1 hour after the pressure gauge reads
-100.7kPa (-755mmHg).
(6) Remove the charging hose and reinstall the charging cap.

5.8. Additional charging

Do not turn on the power unless all operations are complete.
After evacuating the system, add refrigerant.
Do not charge the system with a refrigerant other than R410A.
Always keep to the limit on the total amount of refrigerant. Exceeding the limit on the
total amount of refrigerant will lead to malfunction during charging of refrigerant.
Do not reuse recovered refrigerant.
Use an electronic scale to measure the charging amount of refrigerant.
Adding more refrigerant than the specifi ed amount will cause a malfunction.
Add refrigerant by charging the system with the refrigerant in the liquid state.
When charging the refrigerant, take into account the slight change in the composition
of the gas and liquid phases, and always charge from the liquid phase side whose com-
position is stable. Adding refrigerant through the gas pipe will cause a malfunction.
CAUTION
CAUTION
CAUTION

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