Page 9
Revised 05−2009
TPA*S4
A − Plumbing
Field refrigerant piping consists of liquid and vapor lines
from the outdoor unit (sweat connections). Use Lennox
L15 (sweat) series line sets as shown in table 2.
TABLE 2
Refrigerant Line Sets
Model
Field
Connections
Recommended Line Set
Liquid
Line
Vapor
Line
Liquid
Line
Vapor
Line
L15
Line Sets
−036
−048
3/8 in.
(10 mm)
7/8 in
(22 mm)
3/8 in.
(10
mm)
7/8 in
(22 mm)
L15−65
15 ft. − 50 ft.
(4.6 m − 15
m)
−060
3/8 in.
(10 mm)
1−1/8 in.
(29 mm)
3/8 in.
(10
mm)
1−1/8 in.
(29 mm)
Field
Fabricated
B − Service Valves
The liquid and vapor line service valves (figures 12 and 13)
and gauge ports are accessible from outside the unit.
Each valve is equipped with a service port. The service ports
are used for leak testing, evacuating, charging and checking
charge. 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.
NOTE-Always keep valve stem caps clean.
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 Liquid or Vapor Line Service Valve:
1 − Remove stem cap with an adjustable wrench.
2 − Using service wrench and hex head extension (5/16 for
vapor line and 3/16 for liquid line), back the stem out
counterclockwise until the valve stem just touches the
retaining ring.
3 − Replace stem cap and 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 − Using service wrench and hex head extension (5/16 for
vapor line and 3/16 for liquid line), turn stem clockwise to
seat the valve. Tighten firmly.
3 − Replace stem cap. Tighten finger tight, then tighten an
additional 1/6 turn.
FIGURE 12
LIQUID LINE SERVICE VALVE (VALVE OPEN)
SCHRADER
®
VALVE
SERVICE
PORT
SERVICE
PORT
CAP
INSERT HEX
WRENCH HERE
TO INDOOR COIL
TO COMPRESSOR
STEM CAP
SCHRADER
®
VALVE OPEN
TO LINE SET WHEN VALVE IS
CLOSED (FRONT SEATED)
SERVICE
PORT
SERVICE
PORT CAP
RETAINING RING
STEM CAP
TO
COMPRESSOR
INSERT HEX
WRENCH HERE
LIQUID LINE SERVICE VALVE (VALVE CLOSED)
VALVE FRONT
SEATED
TO INDOOR COIL
SUCTION LINE (BALL TYPE) SERVICE VALVE
(VALVE OPEN)
FIGURE 13
SCHRADER
®
CORE
SERVICE PORT
SERVICE
PORT
CAP
STEM CAP
FROM INDOOR COIL
TO COMPRESSOR
STEM
USE ADJUSTABLE WRENCH
ROTATE STEM CLOCKWISE 90
_
TO CLOSE
ROTATE STEM COUNTER-CLOCKWISE 90
_
TO OPEN
BALL
(SHOWN OPEN)
