Vacuuming The Piping & The Indoor Unit; Removing Air From The Tubing And Indoor Unit - Fedders R407C Service Manual

Checking for gas leakage
• Connect the Manifold gauge to the
outdoor unit gas line port as shown
on the right.
• Connect the charging cylinder to the
Manifold gauge and open the valve of
the Cylinder.
• Open the low pressure valve of the
Manifold gauge until the meter reads
steady at about 150-200 psig.
• Check for gas leakage especially
around the tubing connectors with a
gas-leak detector.
• If leakage was found, retighten the connector with Torque wrench and repeat
the gas leakage check again.
• Upon completion of the leak test, close the valve of the charging cylinder and
low side valve of the manifold gauge. Remove charging cylinder. Recover
refrigerant from indoor unit and piping through the manifold gauge.

Removing air from the tubing and indoor unit

It is necessary to remove all air from the Refrigeration Cycle, as this air con-
tains moisture, which may cause a malfunction or ineffectiveness of the com-
pressor.
• Connect the center hose of the
Manifold gauge to the vacuum
pump.
• Connect the Manifold gauge to the
outdoor unit gas line port as shown.
• Turn the vacuum pump on for about
10-15 minutes in order to evacuate
the air.
• Close the manifold valve, then turn
off the vacuum pump and disconnect
the hose.
VACUUMING THE PIPING & THE INDOOR UNIT
Vacuum
pump
Manifold gauge
Charging
Cylinder
3-way
valve
3-way
valve
Manifold gauge
C15