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
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.
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