York R-410A - Selection of Vacuum Pump; Vacuum Dry for Refrigerant Pipe

Installation
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4.6.7 Vacuum dry for refrigerant pipe
1) Vacuum Dry: use vacuum pump to change the moisture (liquid) into steam (gas) in the
pipe and discharge it out of the pipe to make the pipe dry. Under one atmospheric pressure, the
boiling point of water (steam temperature) is 100℃. Use vacuum pump to make the pressure in
the pipe near vacuum state, the boiling point of water falls relatively. When it falls under outdoor
temperature, the moisture in the pipe will be vaporized.
2) Selection of vacuum pump
♦ Select the vacuum pump. (Normally the anticipative demand achieves -755mmHg)
♦ Big discharge volume (over 40l/min). Check the vacuum calculator before operation to
make sure its measure range achieve below -755mmHg.
Boiling point of water (℃)
Gas pressure (mmHg) Vacuum degree (mmHg)
40 55 -705
30 36 -724
26.7 25 -735
24.4 23 -737
22.2 20 -740
20.6 18 -742
17.8 15 -745
15.0 13 -747
11.7 10 -750
7.2 8 -752
0 5 -755