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31-EN 32-EN
■ Vacuum drying
• Be sure to perform vacuuming from both liquid and gas sides.
• Be sure to use a vacuum pump equipped with the counter-flow prevention function so that oil in the pump will
not flow back into piping for air conditioners. (If oil in the vacuum pump enters in the air conditioner with R410A
refrigerant, a problem may be caused in the refrigerating cycle.)
After finishing the airtight test and discharging nitrogen gas, connect the gauge manifold to the service ports of the
liquid side, gas side, and balance pipe side and connect a vacuum pump as shown in the figure below. Be sure to
perform vacuuming for the liquid, gas, and balance pipe sides.
P
VL VH
Connected to indoor unit
To outdoor unit
Gas-side valve
Gas-side
service port
Piping at site
Piping at site
Piping at site
Balance
valve
Balance
service port
Liquid-side valve
Liquid-side service port
To gauge manifold
Packed valve details
To
outdoor
unit
Packed valve fully closed
(gas side)
Low pressure
gauge
High pressure
gauge
Gauge
manifold
Vacuum pump
Header outdoor unit
Service port
Service port
Service port
Packed valve fully closed
(liquid side)
Packed valve fully closed
(balance)
Follower units
Brazed
Fully
closed
Fully
closed
Main piping
• Use a vacuum pump with a high vacuuming degree [-100.7kPa (5Torr, -755mmHg)] and large exhaust gas
amount (40L/minute or larger).
• Perform vacuuming for 2 or 3 hours, though the time differs depending on the pipe length. Check that all the
packed valves at the liquid side, gas side, and balance pipe side are fully closed.
• If the pressure does not reach -100.7kPa or less, continue vacuuming for 1 hour or more. If the pressure does
not reach -100.7kPa after 3 hours of vacuuming, stop vacuuming and check for air leakage.
• If the pressure reaches -100.7kPa or less after vacuuming for 2 hours or more, close the valves VL and VH on
the gauge manifold fully and stop the vacuum pump. Leave it as it is for 1 hour to confirm that the vacuuming
degree does not change.
If the degree of vacuum loss is large, moisture may remain in the pipes. In that case, inject dry nitrogen gas and
apply pressure to 0.05MPa and perform vacuuming again.
• After finishing the above procedure of vacuuming, exchange the vacuum pump with a refrigerant canister and
advance to the additional charging of refrigerant.
■ Adding refrigerant
After finishing vacuuming, exchange the vacuum pump with a refrigerant canister and start additional charging of
refrigerant.
Calculation of additional refrigerant charge amount
Refrigerant charge amount at shipment from the factory does not include the refrigerant for pipes at the local site.
For refrigerant to be charged in pipes at the local site, calculate the amount and charge it additionally.
NOTE
If the additional refrigerant amount indicates minus as the result of calculation, use the air conditioner without
additional refrigerant.
Outdoor
unit type
MAP080 MAP100 MAP120 MAP10A MAP12A MAP140 MAP160 MAP14A MAP16A MAP180 MAP200
Charged
amount (kg)
11.5
Additional refrigerant charge amount at site = [1] + [2] + [3]
[1]. Compensation by system HP (Table 1)
[2]. Additional refrigerant charge amount Indoor unit (Table 2)
[3]. (Real length of liquid pipe × Additional refrigerant charge amount per liquid pipe 1 m (Table 3)) × 1.2
Table 1
System Combination Charged refrigerant
Compensation by
System HP
HP HP kg kg
Standard model
8 8 – – 11.5 -3.5
10 10 – – 11.5 -3.5
12 12 – – 11.5 -1.5
14 14 – – 11.5 -1
16 16 – – 11.5 -0.5
18 18 – – 11.5 1.5
20 20 – – 11.5 1.5
22 12 10 – 23 -7
24 12 12 – 23 -3
26 14 12 – 23 -2.5
28 14 14 – 23 -3
30 16 14 – 23 -1.5
32 16 16 – 23 -1
34 18 16 – 23 1
36 18 18 – 23 3
38 20 18 – 23 3
40 20 20 – 23 3
42 14 14 14 34.5 -4.5
44 16 14 14 34.5 -4.5
46 16 16 14 34.5 -6.5
48 16 16 16 34.5 -6.5
50 18 16 16 34.5 -0.5
52 18 18 16 34.5 1.5
54 20 20 14 34.5 1.5
56 20 20 16 34.5 2.5
1117101401-3_EN.indd 161117101401-3_EN.indd 16 1/12/16 3:41 PM1/12/16 3:41 PM
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