16
VACUUM PUMPING
Humid air left inside the refrigerant circuit can cause compressor malfunction. After having connected the
indoor and outdoor units, bleed the air and humidity from the refrigerant circuit using a vacuum pump.
1. Unscrew and remove the caps from the 2-way
and 3- way valves.
2. Unscrew and remove the cap from the service
valve.
3. Connect the vacuum pump hose to the
service valve.
4. Operate the vacuum pump for 10-15 minutes
until an absolute vacuum of 3/8" (10 mm) Hg
has been reached.
5. With the vacuum pump still in operation,
close the low-pressure knob on the vacuum
pump coupling. Stop the vacuum pump.
6. Open the 2-way valve by 1/4 turn and then
close it after 10 seconds. Check all the joints
for leaks using liquid soap or an electronic
leak device.
7. Turn the body of the 2-way and 3-way valves.
Discon-nect the vacuum pump hose.
8. Replace and tighten all the caps on the valves.
Service
inlet
(2) Turn
(8) Secure
(8) Secure
(8) Secure
(2) Turn
Valve cap
Valve cap
(2) Turn
Connect to the
indoor unit
(7) Turn to
open fully
(7) Turn to open fully
(6) Open by 1/4 turn
2-way valve
3-way valve
Refrigerant fluid
direction offlow
INDOOR
UNIT
Vacuum pump
Vacuum pump
Vacuum pump
