Piper Arrow IV Turbo Maintenance Manual page 143

WITH A CHARGING STAND.
This is the preferred method of charging the system.
The following instructions apply to Kent Moore, J23500 charging
stand. (Refer to Figure 21-10.)
1. With the system discharged and evacuated, proceed to hook-up the charging stand. (Refer to Figure
21-11.)
2. Fill the charging cylinder by opening the valve at the base of the charging cylinder and filling the sight
glass with two pounds of liquid refrigerant.
3. As refrigerant stops filling the sight glass, open the valve at the top of the gauge neck assembly
intermittently to relieve head pressure and allow refrigerant to continue filling the sight glass to the required
amount.
4. When refrigerant reaches the required level in the sight glass, close both the valve at the base of the
cylinder and the valve at the bottom of refrigerant tank. Be sure the top valve is fully closed.
If bubbling occurs in sight glass, reopen the cylinder base valve
momentarily to equalize drum and cylinder pressure.
5. Connect the heating element plug to a 110-volt outlet.
6. Turn cylinder sight glass to match pressure reading on cylinder pressure gauge. This scale should be
used during entire charging operation.
7. Close valve 1 (low pressure control), fully open valve 4 (refrigerant control) and allow all the liquid
refrigerant contained in the charging cylinder to enter high side of aircraft system.
8. When the full charge of refrigerant has entered the system, close valve 4 (refrigerant control) and valve
2 (high pressure control).
9. After completion of charging, close all valves on the charging stand. Disconnect the high and low
pressure charging lines from the aircraft system. (A small amount of refrigerant remaining in the lines will
escape.) Replace lines on holder of charging stand to keep air and dirt out of lines. Open the valve at the top of
cylinder to relieve any remaining pressure, then reclose the valve.
10. Reinstall protective caps of Schrader valves and any access panels previously removed.
USING THE AIRPLANE COMPRESSOR TO CHARGE THE SYSTEM.
This method is the least desirable due to the requirement of operating the airplane's engine to run the
compressor.
If the air conditioner is to be operated during ground servicing,
the test area should be clean and free of any loose objects lying
on the ramp. Only the service valve located on the evaporator
assembly should be used for testing.
PIPER AIRCRAFT
PA-28RT-201 / 201T
MAINTENANCE MANUAL
—NOTE—
—NOTE—
—WARNING—
1F23
21-50-14
Page 21-24
December 1, 1978