Leak Test And Vacuum Drying; Additional Refrigerant Charge - Daikin RMXS112D7V3B Installation Manual

RMXS112~160D7V3B
Super Multi Plus System air conditioner
4PW19516-1B

9.8. Leak test and vacuum drying

The units were checked for leaks by the manufacturer.
See figure 6 and refer to "Additional refrigerant charge" on page 10
for nomenclature of the parts in figure 6.
• Confirm that the gas and liquid line stop valves are firmly closed
before pressure test or vacuuming.
• Make sure that valve A is completely open.
Air tight test and vacuum drying
Air tight test: Make sure to use nitrogen gas. (For the service
port position, refer to "9.2. Cautions for handling stop valve" on
page 7.
Pressurize the liquid and gas pipes to 4.0 MPa (40 bar) (do not
pressurize more than 4.0 MPa (40 bar)). If the pressure does not
drop within 24 hours, the system passes the test. If the pressure
drops, check where the nitrogen leaks from.
Vacuum drying: Use a vacuum pump which can evacuate to
–100.7 kPa (5 Torr, –755 mm Hg)
1. Evacuate the system from the liquid and gas pipes by using a
vacuum pump for more than 2 hours and bring the system to
–100.7 kPa. After keeping the system under that condition for
more than 1 hour, check if the vacuum gauge rises or not. If it
rises, the system may either contain moisture inside or have
leaks.
2. Following should be executed if there is a possibility of moisture
remaining inside the pipe (if piping work is carried out during the
raining season or over a long period of time, rainwater may enter
the pipe during work).
After evacuating the system for 2 hours, pressurize the system to
0.05 MPa (vacuum break) with nitrogen gas and evacuate the
system again using the vacuum pump for 1 hour to –100.7 kPa
(vacuum drying). If the system cannot be evacuated to –100.7 kPa
within 2 hours, repeat the operation of vacuum break and vacuum
drying.
Then, after leaving the system in vacuum for 1 hour, confirm that
the vacuum gauge does not rise.

9.9. Additional refrigerant charge

Refrigerant cannot be charged until field wiring has been
completed.
Refrigerant may only be charged after performing the leak
test and the vacuum drying (see above).
When charging a system, care shall be taken that its
maximum permissible charge is never exceeded, in view of
the danger of liquid hammer.
Charging with an unsuitable substance may cause
explosions and accidents, so always ensure that the
appropriate refrigerant (R-410A) is charged.
Refrigerant containers shall be opened slowly.
Always use protective gloves and protect your eyes when
charging refrigerant.
See figure 6.
1 Presssure reducing valve
2 Nitrogen
3 Tank
4 Siphon system
5 Measuring instrument
6 Vacuum pump
7 Valve A
8 Gas line stop valve
9 Outdoor unit
10 Liquid line stop valve
11 Indoor unit
12 Stop valve service port
13 Charge hose
14 BP unit
Installation manual
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