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B−Liquid and Vapor Line Service Valves
The liquid line and vapor line service valves and gauge
ports are accessible from outside of the unit. Full service
liquid and vapor line valves are used. The service ports are
used for leak testing, evacuating, charging and checking
charge.
A full-service liquid and vapor line valve made by one of
several manufacturers may be used. All liquid and vapor
line service valves function the same way, differences are
in construction. Valves manufactured by Parker are forged
assemblies. Valves manufactured by Primore are brazed
together. Valves are not rebuildable. If a valve has failed it
must be replaced. The liquid line service valve is illustrated
in figure16. The vapor line service valve is illustrated in fig-
ure17.
The valves are equipped with a service port. A schrader
valve is factory installed. A service port cap is supplied to
protect the schrader valve from contamination and serve
as the primary leak seal. Service port cap must be in place
and turned 1/8 to 1/4 turn to assure proper seal.
NOTE− Always keep valve stem clean.
FIGURE 16
LIQUID LINE SERVICE VALVE (VALVE OPEN)
SCHRADER
VALVE
SERVICE
PORT
SERVICE
PORT
CAP
INSERT HEX
WRENCH HERE
FIELD SIDE
UNIT SIDE
STEM CAP
SCHRADER VALVE OPEN
TO LINE SET WHEN VALVE IS
CLOSED (FRONT SEATED)
SERVICE
PORT
SERVICE
PORT CAP
RETAINING RING
STEM CAP
INSERT HEX
WRENCH HERE
LIQUID LINE SERVICE VALVE (VALVE CLOSED)
(VALVE FRONT SEATED)
FIELD SIDE
UNIT SIDE
To Access Schrader Port:
1 − Remove access panel.
2 − Remove service port cap with an adjustable wrench.
3 − Connect gauge to the service port.
4 − When testing is completed, replace service port cap.
Tighten finger tight, then an additional 1/6 turn.
To Open Liquid or Vapor Line Service Valve:
1 − Remove stem cap with an adjustable wrench.
2 − For liquid line valve use service wrench and 3/16 hex
head extension. Back the stem out counterclockwise
until the valve stem just touches the retaining ring. For
vapor line valve use adjustable wrench and back the
stem out counterclockwise 1/4 turn.
3 − Replace stem cap tighten firmly. Tighten finger tight,
then tighten an additional 1/6 turn.
Do not attempt to backseat this valve. Attempts to
backseat this valve will cause snap ring to explode
from valve body under pressure of refrigerant.
Personal injury and unit damage will result.
DANGER
To Close Liquid or Vapor Line Service Valve:
1 − Remove stem cap with an adjustable wrench.
2 − For liquid line valve use service wrench and 3/16 hex
head extension. Turn stem clockwise to seat valve.
Tighten firmly. For vapor line valve use adjustable
wrench and turn stem clockwise 1/4 turn to seat valve.
Tighten firmly.
3 − Replace stem cap. Tighten finger tight, then tighten an
additional 1/6 turn.
FIGURE 17
VAPOR LINE (BALL TYPE) SERVICE VALVE
(VALVE OPEN)
SERVICE PORT
SERVICE PORT
CAP
STEM CAP
INLET
(FROM INDOOR COIL)
OUTLET
(TO COMPRESSOR)
STEM
USE ADJUSTABLE WRENCH
ROTATE STEM CLOCKWISE 90
TO CLOSE
ROTATE STEM COUNTER-CLOCKWISE 90
TO OPEN
BALL
(SHOWN OPEN)
SCHRADER VALVE
