Lennox Dave Signature XP21 Installation Instructions Manual page 15

STEP 5 -- REFRIGERANT PIPING -- Brazing Procedures
1
PIPING PANEL REMOVAL / PREPARING LINE SET
Remove piping panel to access service valves. Cut
ends of the refrigerant lines square (free from nicks or
dents) and debur the ends. The pipe must remain
round. Do not crimp end of the line.
CUT AND DEBUR
SERVICE VALVE
CONNECTION
COPPER TUBE
STUB
REDUCER
REFRIGERANT LINE
DO NOT CRIMP SERVICE
VALVE CONNECTOR WHEN
PIPE IS SMALLER THAN
CONNECTION
3
ATTACH THE MANIFOLD GAUGE SET FOR BRAZING
LIQUID AND VAPOR LINE SERVICE VALVES
A Connect gauge set low pressure side to liquid line service valve (service port).
B Connect gauge set center port to bottle of nitrogen with regulator.
C With valve core removed from the vapor line service port, nitrogen flow will have an exit point.
VAPOR SERVICE PORT MUST BE OPEN AND
SERVICE PORT CORE REMOVED TO ALLOW
EXIT POINT FOR NITROGEN FLOW
INDOOR
UNIT
LINE SET SIZE MATCHES
SERVICE VALVE CONNECTION
LINE SET SIZE IS SMALLER
THAN CONNECTION
C
VAPOR LINE
LIQUID LINE SERVICE
LIQUID LINE
2
CAP AND CORE REMOVAL
Remove service cap and core from both the vapor
and liquid line service ports.
VAPOR LINE SERVICE
VALVE
LOW HIGH
ATTACH
GAUGES
B
VAPOR LINE
SERVICE
VALVE
OUTDOOR
UNIT
A
VALVE
FIGURE 14
Page 15
SERVICE PORT CAP
SERVICE PORT
CORE
LIQUID LINE SERVICE VALVE
SERVICE PORT
CORE
SERVICE
PORT CAP
NITROGEN
XP21 SERIES