6
Step 2. Evacuate Lines And Indoor Coil.
a. Open the high and low side valves (B & A) on the gauge
manifold.
NOTE:
Only open the valve (E) on the
gauge manifold leading to the cylinder, not the valve
on the charging cylinder (F).
b. Evacuate the system to about 29 inches Hg as mea-
sured by the low side (compound) gauge.
c. Open the valve (D) to the vacuum gauge. Evacuate
until the gauge reads 250 microns or less.
d. Close the valve to the vacuum pump (C). Wait five
minutes, then check the pressure on the vacuum
gauge:
1. If the pressure is not more than 1500 microns, the
system is leak-free and properly evacuated. Pro-
ceed to step (e).
2. If the pressure rises, but holds at about 5000 mi-
crons, moisture and noncondensibles are still
present. Open the valve to the vacuum pump (E),
and go back to step (c).
3. If the pressure rises above 5000 microns, a leak is
present. Go back to “Leak Testing” section on page
4.
e. Close the valve to the vacuum gauge.
f. Close the valve to the vacuum pump. Shut off the
pump.
