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A−Service Valves
Access the liquid line and vapor line service valves (figures
18 and 19) and gauge ports are used for leak testing, eva-
cuating, charging and checking charge. See table 7 for
torque requirements.
Each valve is equipped with a service port which has a fac-
tory−installed Schrader valve. A service port cap protects
the Schrader valve from contamination and serves as the
primary leak seal.
TABLE 7
Part
Recommended Torque
Service valve cap
8 ft.− lb.
11 NM
Sheet metal screws
16 in.− lb.
2 NM
Machine screws #10
28 in.− lb.
3 NM
Compressor bolts
90 in.− lb.
10 NM
Gauge port seal cap
8 ft.− lb.
11 NM
IMPORTANT
Service valves are closed to the outdoor unit and
open to line set connections. Do not open the valves
until refrigerant lines have been leak tested and
evacuated. All precautions should be exercised to
keep the system free from dirt, moisture and air.
To Access Schrader Port:
1 − Remove service port cap with an adjustable wrench.
2 − Connect gauge to the service port.
3 − When testing is complete, replace service port cap.
Tighten finger tight, then an additional 1/6 turn.
To Open Service Valve:
1 − Remove stem cap with an adjustable wrench.
2 − Using service wrench and hex head extension, back
the stem out counterclockwise as far as it will go.
NOTE − Use a 3/16" hex head extension for liquid line
size.
3 − Replace stem cap and tighten it firmly. Tighten finger
tight, then tighten an additional 1/6 turn.
To Close Service Valve:
1 − Remove stem cap with an adjustable wrench.
2 − Using service wrench and hex head extension, turn
stem clockwise to seat valve. Tighten it firmly.
NOTE − Use a 3/16" hex head extension for liquid line
size.
3 − Replace stem cap. Tighten finger tight, then tighten an
additional 1/6 turn.
Vapor Line (Ball Type) Valve
Vapor line service valves function the same way as the oth-
er valves, the difference is in the construction. These
valves are not rebuildable. If a valve has failed, you must
replace it. A ball valve valve is illustrated in figure 19.
The ball valve is equipped with a service port with a factory−
installed Schrader valve. A service port cap protects the
Schrader valve from contamination and assures a leak−
free seal.
Liquid Line Service Valve
(Valve Closed)
(valve front seated)
to
indoor coil
to outdoor coil
service
port cap
insert hex
wrench here
stem cap
service port
Liquid Line Service Valve
(Valve Open)
schrader
valve
service port
service
port cap
insert hex
wrench here
to
indoor coil
to outdoor coil
stem
cap
Service Port Is Open
To Line Set When Valve Is
Closed (Front Seated)
FIGURE 18
Vapor Line (Ball Type) Service Valve
(Valve Open)
Schrader
valve
stem cap
Use Adjustable Wrench
To open: rotate stem counter-clockwise 90°.
To close: rotate stem clockwise 90°.
ball
(shown open)
service port
cap
service
port
field side
unit side
stem
FIGURE 19
