Lennox CBX25UHV Series Installation And Service Procedure page 20

INSTALL CONDENSATE DRAIN
The air handler is equipped with ¾" NPT condensate drain
connections.
IMPORTANT
On some pans, the primary and secondary drain holes
have knockouts.
Confirm primary and secondary drains are open.
1. CB25UHV-018 through -036 units are equipped with
a white drain pan, which includes green (main drain)
and red (secondary drain) plugs. Unscrew the plugs to
remove them before inserting condensate drain
fittings.
2. CB25UHV-042 through -60 units are equipped with a
black drain pan equipped with drain knockouts. Use a
flat-blade screwdriver to remove the ¾" main drain and
⅜" secondary drain knockouts. Remove all rough
edges before inserting condensate drain fittings.
CBX25UHV-018 THROUGH -036 MODELS
UNSCREW PLUGS
AND CONNECT
PROPERLY SIZED
FIELD-PROVIDED
FITTINGS AND
DRAIN LINES.
WHITE DRAIN GREEN MAIN
PAN DRAIN PLUG
CBX25UHV-042 THROUGH -060 MODELS
¾" MAIN DRAIN
KNOCKOUT
BLACK DRAIN
PAN
Figure 31. Drain Line Connections
3. Install properly sized, field-provided connection fittings
and connect primary drain line to the main drain pan
connection.
RED SECONDARY
DRAIN PLUG
⅜"SECONDARY
DRAIN KNOCKOUT
USE FLATHEAD SCREWDRIVER TO
REMOVE KNOCKOUTS, REMOVE
ROUGH EDGES AND CONNECT
PROPERLY SIZED FIELD-PROVIDED
FITTINGS AND DRAIN LINES.
NOTE - When installing drain line connection fittings to
the drain pan, hand tighten the fitting and use a thread
sealant. Over-tightening
connections on the drain pan.
4. If the secondary drain line is to be used, remove the
plug or the knockout and route the drain line so that
water draining from the outlet will be easily noticed by
the homeowner. Refer to local codes for drain trap
requirements on the secondary drain line.
5. Check again to ensure drain ports and drain pan are
free of all debris.
6. Plug and check any unused drain pan openings for
tightness. Torque plugs to 30 in. lb. to prevent water
leaks or seepage from the drain pan.
7. Install a 2" trap in the main (primary) drain lines as close
to the unit as practical (see figure 32). Make sure the
top of the trap is below the connection to the drain pan
to allow complete drainage of the pan.
NOTE - Horizontal runs must have an anti-siphon air
vent (standpipe) installed ahead of the horizontal run.
See figure 32. An extremely long horizontal run may
require an oversized drain line to eliminate air traps.
NOTE - Do not operate air handler without a trap in the
main (primary) drain. The condensate drain is on the
negative pressure side of the blower; therefore, air
being pulled through the condensate line will not allow
positive drainage without a proper trap.
8. Route the drain line to the outside or to an appropriate
drain. Drain lines must be installed so they do not block
service access to the front of the air handler. A 24"
clearance is required for filter, coil, or blower removal
and service access.
NOTE - Check local codes before connecting the drain
line to an existing drainage system.
Insulate the drain lines where sweating could cause water
damage.
TEST CONDENSATE DRAIN
Test the drain pan and drain line after installation:
1. Pour several quarts of water into drain pan, enough to
fill drain trap and line.
2. Check to make sure the drain pan is draining
completely, no leaks are found in drain line fittings, and
water is draining from the end of the primary drain line.
3. Correct any leaks found.
Page 20
the fittings can split