PTEC-M-1A
26
Refrigeration
System
Evacuation
WARNING!
To prevent severe burns, do not
allow the sludge or oil to contact the
skin.
Important Note:
Effective July 1,1992. Before opening
any refrigerant system it is the
responsibility of the service
technician to capture the refrigerant
for safe disposal.
This is the most important part of the
entire service procedure. The life and
efficiency of the equipment is
dependent upon the thoroughness
exercised by the serviceman when
evacuating air (non-condensables)
and moisture from the system.
Air in the system causes high
condensing temperature and
pressure, resulting in increased
power input and reduced
performance.
Moisture chemically reacts with the
refrigerant and oil to form corrosive
hydrofluoric and hydrochloric acids.
These attack motor windings and
parts, causing breakdown.
The equipment required to
thoroughly evacuate the system is a
high vacuum pump, capable of
producing a vacuum equivalent to
50 microns, and a thermocouple
vacuum gauge to give a true reading
of the vacuum in the system.
Note:
Never use the system
compressor as a vacuum pump or
run when under a high vacuum.
Motor damage could occur.
1. Connect the vacuum pump,
vacuum tight manifold set with high
vacuum hoses, thermo-couple
vacuum gauge and charging
cylinder.
2. Connect the low side line to the
process tube of the compressor.
3. Connect the high side line to the
process tube of liquid line strainer.
Note:
If either process tube is not
long enough to receive the
compression or flare fitting and still
leave room for a pinch-off, swag the
tube and braze in an extra length of
tubing.
4. Start the vacuum pump and open
shut off valve to the high vacuum
gauge manifold only. After the
compound gauge (low side) has
dropped to approximately 29
inches of vacuum open the valve
to the vacuum thermocouple
gauge. See that the vacuum pump
will bank-off to a minimum of 50
microns. A high vacuum pump
can only produce a good vacuum
if its oil is not contaminated.
5. If the vacuum pump is working
properly, close the valve to the
vacuum thermocouple gauge and
open the high and low side valves
or the high vacuum manifold set.
With the valve on the charging
cylinder closed, open the manifold
valve to the cylinder.
6. Evacuate the system to at least 29
inches gauge be fore opening
valve to thermocouple vacuum
gauge.
7. Continue to evacuate to a
minimum of 250 microns. Close
valve pump and watch rate of rise.
If vacuum does not rise above
1500 microns in three minutes,
system can be considered
properly evacuated.
8. If thermocouple vacuum gauge
continues to rise and levels off at
about 5000 microns, moisture and
non-condensables are still
present. If gauge continues to rise
a leak is present. Repair and re-
evacuate.
Содержание PTEC-070
Страница 22: ...PTEC M 1A 22 Refrigeration System PTEC Refrigeration System...
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Страница 55: ...55 PTEC M 1A Schematic Diagrams PTEC and PTHC Condensate Pump Two Stage Heat...
Страница 56: ...PTEC M 1A 56 Schematic Diagrams PTEC and PTHC Power Vent One Stage Heat...
Страница 57: ...57 PTEC M 1A Schematic Diagrams PTEC and PTHC Power Vent Two Stage Heat...
Страница 58: ...PTEC M 1A 58 PTEC and PTHC Power Door One Stage Heat Schematic Diagrams...
Страница 59: ...59 PTEC M 1A Schematic Diagrams PTEC and PTHC Power Door Two Stage Heat...
Страница 60: ...PTEC M 1A 60 Schematic Diagrams PTEC and PTHC Condensate Pump with Power Vent One Stage Heat...
Страница 61: ...61 PTEC M 1A Schematic Diagrams PTEC and PTHC Condensate Pump with Power Vent Two Stage Heat...
Страница 62: ...PTEC M 1A 62 Schematic Diagrams Hydronic...
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