RS1200001 16 November 1996
HFC134a Service Information
Before opening system evaporator coil must be at
ambient temperature to minimize moisture infiltration
into system.
1. After capturing refrigerant, replacing drier and
making any repairs, evacuate system from high
side through drier/process tube and low side
through compressor process tube simultaneously.
Evacuation should not be done through line
piercing valve but through I.D. opening of tubes.
2. With valves “C” and “F” closed to thermistor
vacuum gauge and charging cylinder, open all
other valves and start vacuum pump.
3. At approximately 29 inches of vacuum, open valve
“C” to thermistor vacuum gauge and take micron
reading.
4. Continue evacuating system until thermistor
vacuum gauge registers 600 microns.
5. At 600 microns close valve “A” to vacuum pump to
allow micron reading in system to balance. Micron
level will rise. If in 2 minutes, micron level
stabilizes at 1000 microns or below, system is
ready for charging.
•If micron rises above 1000 micron level and
stabilizes, open valve “A” to vacuum pump and
continue evacuating.
•If micron reading rises rapidly and does not
stabilize, a leak still exists in system. Close valve
“A” to vacuum pump and “C” to thermistor vacuum
gauge. Invert charging cylinder and open charging
cylinder valve “F” to add partial charge for leak
checking. With leak detector, check manifold
connections and system for leaks. After locating
leak, capture refrigerant charge, repair leak, and
begin at step 1.
6. Once system is ready to charge, close valve “A”
(vacuum pump), “C” (thermistor vacuum gauge),
and “E” (low side manifold gauge).
7. Check serial plate for correct charge and set scale
on dial-a-charge cylinder for corresponding
HFC134a pressure reading. Do not use captured or
recycled refrigerant in Amana® refrigerators. Use
of captured or recycled refrigerant voids any
warranty.
8. Open valve “F” to charging cylinder and let exact
amount of refrigerant out of cylinder. Close valve.
Low side gauge pressure should rise shortly after
opening charging cylinder valve as system
pressure equalizes through capillary tube. If
pressure does not equalize, a restriction typically
exists at capillary/drier braze joint.
WARNING
To avoid severe personal injury or death from
fire keep system free from contamination due
to presence of air. Follow instructions exactly.
9. If no restriction exists, open valve “E” (low side
manifold gauge) and pinch off high side drier
process tube.
10. Start compressor and draw remaining refrigerant
in charging hoses and manifold into compressor
through compressor process tube. To check high
side pinch-off drier process tube, close valve “D”
(high side gauge). If pinch-off is not leaking, high
side pressure will not rise. If high side pressure
gauge shows an increase, repeat high side pinch-
off and open valve “D”. Repeat until high side
pinch-off no longer leaks.
11. Pinch-off compressor process tube and remove
charging hose. Braze stub closed while
compressor is operating.
12. Unplug refrigerator from electrical outlet.
Remove charging hose and braze high side drier
process tube closed.