AF-A097E
Piston Type Compressor No good.
System parts must be above 43 uC.
DIAL-CHARGE
Rotary Vacuum Pump Disavantages.ELECTRICCHARGING CYLINDER
VACUUM
Low CFMC. 4 oil gets dirty.GAUGE
LOW SIDEHIGH SIDE
GAUGEGAUGE
Single State Vacuum Pump will not clean oil.
Oil must be changed often.
HIGH VACUUM
TO RELATED SERVICE
VALVE OR PROCESSMANIFOLD
2 Stage Vacuum Pump will reach 50 microns.TUBES OF THE UNIT.
First stage is below atmospheric pressure.
LARGE DIAMETER
Moisture is removed into second stage which works up toBRAIDED VACUUM
HOSES
atmospheric pressure thus keeping oil clean.
Manometer cannot be read to 1/2 mm. Micron gauge
reads from 25,400 microns to 0.
Hook up for Evacuation and chargingHIGH VACUUM PUMP
Figure 5
It becomes clear that good equipment and maintained properly must be used in order to remove air and moisture from the
system.
When a vacuum of 1,000 to 500 microns is reached, block off the vacuum pump from the system.
This is done by closing the value between the pump and system. If the micron gauge does not increase above 1,000, the
system is free of moisture and no leak exists. If the micron gauge increases to higher levels moisture or a leak exists.
LEAKS
Several methods are used to detect leaks in systems.
Electric Leak Detectors are very sensitive and are able to detect leaks down to 1/2 ounce per year.
A good electronic leak detector is generally for better in locating very small leaks.
Halide Torch be sure the room is free from refrigerant vaports. Watch the flame for the slightest change in color.
A very faint green indicates a small leak. The flame will be unmistakably changed to green or purple when large leaks
are encountered. To simplify leak detection pressurize the system to approximately 75 lbs.
Some leaks can be located by a visual inspection of the system components and points and if oil is found at any given
location it generally is a sign that a leak exists at that point due to the fact that flame does carry oil with it travels
throughthe system.
Soap Bubbles
Liquid detergents can sometimes assist in finding small leaks by brushing detergent on the suspect area and
watching for bubbles. Before applying detergent be sure that the system is pressurized.
Tap line devices are permissible for diagnosis only they are not suitable when evacuating the system. After the diagnosis
has been made they must be removed so that the system will be restored to a hermeticly sealed condition.
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ACEC
