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To Access Service Port:
1– Remove the stem cap. Use a service wrench
(part #18P66, 54B64 or 12P95) to make sure the ser-
vice valve is backseated.
CAUTION
The service port cap is used to seal the liquid line
service valve. Access to service port requires
backseating the service valve to isolate the
service port from the system. Failure to do so
will cause refrigerant leakage.
IMPORTANT
A schrader valve is not provided on the liquid line
service port. Valve must be backseated to turn off
pressure to service port.
2– Remove service port cap and connect high pressure
gauge to service port.
3– Using service wrench, open valve stem (one turn
clockwise) from backseated position.
4– When finished using port, backseat stem with ser-
vice wrench. Tighten firmly.
5– Replace service port and stem cap. Tighten finger
tight, then tighten an additional 1/6 turn.
To Close Off Service Port:
1– Using service wrench, backseat valve.
a – Turn stem counterclockwise.
b – Tighten firmly.
To Open Liquid Line Service Valve:
1– Remove the stem cap with an adjustable wrench.
2– Using service wrench, backseat valve.
a – Turn stem counterclockwise until backseated.
b – Tighten firmly.
3– Replace stem cap, finger tighten then tighten an
additional 1/6 turn.
To Close Liquid Line Service Valve:
1– Remove the stem cap with an adjustable wrench.
2– Turn the stem in clockwise with a service wrench to
front seat the valve. Tighten firmly.
3– Replace stem cap, finger tighten then tighten an
additional 1/6 turn.
2 – Suction Line (Seating Type) Service Valve
A full service non-backseating suction line service valve
is used on all HS25 series units. Different manufacturers
of valves may be used. All suction line service valves
function the same way, differences are in construction.
Valves manufactured by Parker are forged assem-
blies. Primore and Aeroquip valves are brazed to-
gether. Valves are not rebuildable. If a valve has
failed it must be replaced. The suction line service
valve is illustrated in figure 8.
The valve is equipped with a service port. A schrader
valve is factory installed. A service port cap is sup-
plied to protect the schrader valve from contamina-
tion and assure a leak free seal.
SUCTION LINE SERVICE VALVE (VALVE OPEN)
FIGURE 8
SCHRADER VALVE
SERVICE PORT
SERVICE PORT
CAP
STEM CAP
SNAP RING
INSERT HEX WRENCH
HERE (PART #49A71 AND
SERVICE WRENCH)
SUCTION LINE SERVICE VALVE (VALVE CLOSED)
INLET
(FROM INDOOR COIL)
OUTLET
(TO COMPRESSOR)
KNIFE EDGE
SEAL
SCHRADER VALVE OPEN
TO LINE SET WHEN
VALVE IS CLOSED
(FRONT SEATED)
SERVICE PORT
SERVICE PORT
CAP
(VALVE
FRONT SEATED)
SNAP RING
STEM
CAP
OUTLET
(TO COMPRESSOR)
KNIFE EDGE SEAL
INLET
(FROM INDOOR COIL)
INSERT
HEX WRENCH HERE
(PART #49A71 AND
SERVICE
WRENCH)
To Access Schrader Port:
1– Remove service port cap with an adjustable wrench.
2– Connect gauge to the service port.
3– When testing is completed, replace service port cap.
Tighten finger tight, then an additional 1/6 turn.
To Open Suction Line Service Valve:
1– Remove stem cap with an adjustable wrench.
2– Using service wrench and 5/16” hex head extension
(part #49A71) back the stem out counterclockwise
until the valve stem just touches the retaining ring.
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
3– Replace stem cap tighten firmly. Tighten finger
tight, then tighten an additional 1/6 turn.
To Close Suction Line Service Valve:
1– Remove stem cap with an adjustable wrench.
2– Use service wrench and 5/16” hex head extension
(part #49A71) turn stem clockwise to seat the valve.
Tighten firmly.
