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Idiomas disponibles
Idiomas disponibles
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Caulk with a nonflammable material such as mortar.
Nonflammable insulation material
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・When caulking the gaps with mortar, cover the section of the pipe that goes through the wall with a metal sheet to prevent the insulation material
from sagging. For this section, use nonflammable insulation and covering materials. (Vinyl tape should not be used.)
9-8. Evacuation of the system
Do not purge the air using refrigerant. Use a vacuum pump to evacuate the system.
- Residual gas in the refrigerant lines will cause bursting of the pipes or an explosion.
Use a vacuum pump with a check valve.
- If the vacuum pump oil flows back into the refrigerant lines, the refrigerant oil may deteriorate and the compressor
may malfunction.
<Evacuation procedures>
① Evacuate the system from both service ports, using a vacuum pump with the service valves closed.
② After the vacuum reaches 650 Pa (abs) (0.0943 psi/5 Torr), continue evacuation for at least one hour. When the outdoor temperature drops
below 1ºC (or when the saturation pressure drops below 656 Pa (abs) (0.0951 psi/5 Torr)), continue evacuation for another 1 hour after the
vacuum degree has reached the saturated vapor pressure of the water (ice) at the outdoor temperature. When performing evacuation at a low
outdoor temperature, use a vacuum gauge appropriate for the temperature range.
Degree of vacuum (reference)
Outdoor temperature
Degree of vacuum
0.77 Torr (103 Pa) 1.24 Torr (165 Pa) 1.95 Torr (260 Pa) 3.01 Torr (402 Pa) 4.58 Torr (611 Pa)
* The degrees of vacuum shown above are obtained based on the saturated vapor pressure of ice.
* In a system using water heat exchangers, circulate water to prevent the water from freezing during evacuation.
③ Stop the vacuum pump and leave it for an hour.
④ Verify that the vacuum has not increased by more than 130 Pa (0.01886 psi/1 Torr).
⑤ If the vacuum has increased by more than 130 Pa, water infiltration is suspected. Pressurize the system with dry nitrogen gas up to 0.05 MPa
(gauge) (7.25 psi/375 Torr). Repeat ① though ⑤ until the vacuum is increased by 130 Pa or below. If the results persist, then perform the
"Triple Evacuation" below.
<Triple Evacuation>
① Evacuate the system to 533 Pa (abs) (0.07729 psi/4 Torr) from both service ports, using a vacuum pump.
② Pressurize the system with dry nitrogen gas up to 0 Pa (gauge) (0 psi/0 Torr) from the discharge service port.
③ Evacuate the system to 200 Pa (abs) (0.029 psi/1.5 Torr) from the suction service port, using a vacuum pump.
④ Pressurize the system with dry nitrogen gas up to 0 Pa (gauge) (0 psi/0 Torr) from the discharge service port.
⑤ Evacuate the system from both service ports, using a vacuum pump.
⑥ After the vacuum reaches 66.7 Pa (abs) (0.09672 psi/5 Torr), stop the vacuum pump and leave it for an hour. A vacuum of 66.7 Pa must be
maintained for at least one hour.
⑦ Verify that the vacuum has not increased for at least 30 minutes.
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LO
HI
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・Use a scale that can measure down to 0.1 kg (0.1 oz).
・Recommended vacuum gauge: ROBINAIR 14830A Thermistor Vacuum Gauge or Micron Gauge
・Do not use a gauge manifold to measure the vacuum pressure.
・Use a vacuum pump capable of attaining a vacuum of 65 Pa (abs) within five minutes of operation.
WT09117X05
-20ºC (-4ºF)
-15ºC (5ºF)
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-10ºC (14ºF)
-5ºC (23ºF)
Gauge manifold
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Low pressure knob
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High pressure knob
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Service valve
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Low-pressure pipe
High-pressure pipe
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Service port
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Three-way joint
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Valve (vacuum pump)
Valve (for charging refrigerant)
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Refrigerant tank
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Scale
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Vacuum pump
To indoor unit
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Outdoor unit
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GB-25
0ºC (32ºF)
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