
Check Points, Maintenance and Troubleshooting
64
Air-to-Water Heat Pump
When selecting a vacuum, you should select one which is capable of achieving 0.2 Torr of ultimate
vacuum.
Degree of vacuum is expressed in Torr, micron, mmHg, and Pascal (Pa). The units correlate as
follows:
Unit
Standard
atmospheric
pressure
Perfect vacuum
Gauge Pressure
Pa
0
-1.033
Absolute Pressure
Pa
1.033
0
Torr
Torr
760
0
Micron
Micron
760000
0
mmHg
mmHg
0
760
Pa
Pa
1013.33
0
2. Charge of refrigerant
You should be charged after vacuum.
You can see amount of refrigerant at quality label.
SVC Port
Manifold gauge
Refrigerant
cylinder