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(4)
Be sure to seal the holes
Putty
when applying the putty.
Place the cables side by
side. (Do not overlap the
cables.)
(5)
Put the service panel and
valve cover back after
completion of the work.
61
PIPE INSTALLATION II
61 11
Vacuum
CAUTION
Always use a vacuum pump to purge the air.
Refrigerant for purging the air is not charged in the outdoor unit at the factory.
Refrigerant must not be discharged into atmosphere.
Use a vacuum pump, gauge manifold and charge hose for R410A exclusively. Using
the same vacuum for different refrigerants may damage the vacuum pump or the unit.
After connecting the piping, check the joints for gas leakage with gas leak detector or
soapy water.
61 11 11
CHECKING GAS LEAKAGE AND PURGING AIR
Gas leak checks are performed using either vacuum or nitrogen gas, so select the proper
one depending on the situation.
Checking gas leaks with vacuum:
(1)
Check if the piping connections are secure.
(2)
Remove the cap of 3-way valve, and connect the gauge manifold charge hoses to the
charging port of the 3-way valve.
(3)
Open the valve of the gauge manifold fully.
(4)
Operate the vacuum pump and start pump down.
(5)
Check that the compound pressure gauge reads -0.1 MPa (76 cmHg), operate the
vacuum pump for 30 minutes or more in each valve.
(6)
At the end of pump down, close the valve of the gauge manifold fully and stop the
vacuum pump.
(It checks that leave as it is for about 10 minutes, and a needle does not return.)
(7)
Disconnect the charge hose from the 3-way valve charging port.
(8)
Remove the blank caps, and fully open the spindles of the 2-way and 3-way valves
with a hexagon wrench.
[torque: 6 to 7 N·m (60 to 70 kgf·cm)].
(9)
Tighten the blank caps and charging port cap of the 2-way valve and 3-way valve to
the specified torque.
Checking gas leaks with nitrogen gas:
(1)
Check if the piping connections are secure.
(2)
Remove the cap of 3-way valve, and connect the gauge manifold charge hoses to the
charging port of the 3-way valve.
(3)
Pressurize with nitrogen gas using the 3-way valve charging port.
(4)
Do not pressurize up to the specified pressure all at once but do so gradually.
2
① Increase the pressure up to 0.5 Mpa (5 kgf/cm
), let it sit for about five minutes
and then check for any decrease in pressure.
2
② Increase the pressure up to 1.5 Mpa (15 kgf/cm
), let it sit for about five minutes
and then check for any decrease in pressure.
③ Increase the pressure up to the specified pressure (the pressure designed for the
product) and then make a note of it.
(5)
Let it sit at the specified pressure and if there is no decrease in pressure then it is
satisfactory. If a pressure decrease is confirmed, there is a leak, so it is necessary to
specify the leak location and make minor adjustments.
(6)
Discharge the nitrogen gas and starting removing the gas with a vacuum pump.
(7)
Open the valve of the gauge manifold fully.
(8)
Operate the vacuum pump and start pump down.
(9)
Check that the compound pressure gauge reads -0.1 MPa (76 cmHg), operate the
vacuum pump for 30 minutes or more in each valve.
(10)
At the end of pump down, close the valve of the gauge manifold fully and stop the
vacuum pump.
(11)
Disconnect the charge hose from the 3-way valve charging port.
(12)
Remove the blank caps, and fully open the spindles of the 2-way and 3-way valves
with a hexagon wrench.
[torque: 6 to 7 N·m (60 to 70 kgf·cm)].
(13)
Tighten the blank caps and charging port cap of the 2-way valve and 3-way valve to
the specified torque.
En-7
Tightening torque
6.35 mm (1/4 in.)
20 to 25 N·m (200 to 250 kgf·cm)
9.52 mm (3/8 in.)
20 to 25 N·m (200 to 250 kgf·cm)
Blank cap
12.70 mm (1/2 in.)
28 to 32 N·m (280 to 320 kgf·cm)
15.88 mm (5/8 in.)
30 to 35 N·m (300 to 350 kgf·cm)
19.05 mm (3/4 in.)
35 to 40 N·m (350 to 400 kgf·cm)
Charging port cap
10 to 12 N·m (100 to 120 kgf·cm)
Hexagon wrench
Blank cap
Gauge manifold
Spindle
Charging port
Lo
Hi
Service hose
Vacuum pump
with valve core
Cap
Service hose
with valve core
Service hose
with valve core
Service hose
with valve core
Service hose
CAUTION
Do not purge the air with refrigerants, but use a vacuum pump to vacuum the
installation! There is no extra refrigerant in the outdoor unit for air purging!
Use a vacuum pump and gauge manifold and charging hose for R410A exclusively.
Using the same vacuum for different refrigerants may damage the vacuum pump or the
unit.
61 21
Additional charging
Refrigerant suitable for a total piping length of 50 m is charged in the outdoor unit at the
factory.
When the piping is longer than 50 m, additional charging is necessary.
For the additional amount, see the table below.
Total piping
50m
60m
70m
length
(164 ft)
(197 ft)
(230 ft)
Additional
250g
500g
25g/m
None
refrigerant
(8.8 oz)
(17.6 oz)
(0.27 oz/ft)
CAUTION
When moving and installing the air conditioner, do not mix gas other than the specified
refrigerant (R410A) inside the refrigerant cycle.
When charging the refrigerant R410A, always use an electronic balance for refrigerant
charging (to measure the refrigerant by weight).
Gas
When charging the refrigerant, take into account the
slight change in the composition of the gas and liquid
R410A
phases, and always charge from the liquid phase side
whose composition is stable.
Liquid
Add refrigerant from the charging valve after the completion of the work.
If the units are further apart than the maximum pipe length, correct operation can not be
guaranteed.
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