Lennox 14HPX-018 Installation Instructions Manual page 9

Inverted HCFC-22 Cylinder
(Contains clean HCFC-22 to be
used for flushing)
RECOVERY CYLINDER
EXISTING VAPOR LINE
VAPOR LINE
SERVICE VALVE
EXISTING LIQUID LINE
LIQUID LINE
SERVICE VALVE
Tank Return Inlet
, Discharge
RECOVERY MACHINE
Low High
Pressure Pressure
NOTE - The inverted HCFC-22 cylinder must
contain at least the same amount of refrigerant
as was recovered from the existing system.
Figure 11. Flushing Connections
8. After all of the liquid refrigerant has been recovered,
switch the recovery machine to vapor recovery so that
all of the HCFC-22 vapor is recovered,
NOTE - A single system flush should remove all of the
mineral oil from the existing refrigerant lines and in-
door coil, A second flushing may be done (using clean
refrigerant) if insufficient amounts of mineral oil were
removed during the first flush, Each time the system
is flushed, you must allow the recovery machine
to pull a vacuum on the system at the end of the
procedure.
9. Close the valve on the inverted HCFC-22 drum and
the gauge set valves. Pump the remaining refrigerant
out of the recovery machine and turn the machine off,
10. Use dry nitrogen to break the vacuum on the refriger-
ant lines and indoor coil before removing the recovery
machine, gauges and HCFC-22 refrigerant drum. Re-
install pressure tap valve cores into 14HPX service
valves.
11. Install the provided check/expansion valve (approved
for use with HFC-410A refrigerant) in the liquid line at
the indoor coil.
14HPX units are used in check expansion valve (CTXV)
systems only. See the Lennox Engineering Handbook for
approved valve match-ups and application information,
NOTE - HFC-410A systems will not operate properly with
an HCFC-22 valve.
Check expansion valves equipped with Chatlefffittingsare
available from Lennox. Refer to the Engineering Hand-
book for applicable check expansion valves for use with
specific match-ups, See table 3 for applicable check ex-
pansion valve kits,
Table 3. Indoor Check Expansion Valve Kits
MODEL Kit Number
14HPX-018, -024, -030 49L24
14HPX-036, -042 49L25
14HPX-048, -060 91 M02
Page 9
14HPX SERIES