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CB(X)26UH SERIES
The coil has a fixed orifice in the liquid line (see figure 9).
Remove the rubber plug from the vapor line of the coil.
STRAINER
LIQUID LINE STUB
DISTRIBUTOR
O−RING
FIXED ORIFICE
Figure 9. Metering Device Installation
Condensate Drain
IMPORTANT
On units of this type, where the blower draws" rather
than blows" air through the coil, traps must be installed
in the condensate drain lines (primary and auxiliary, if
used). Traps prevent the blower from drawing air through
the drain lines into the air supply.
IMPORTANT
A field−fabricated secondary drain pan, with a drain pipe
to the outside of the building, is required in all installations
over a finished living space or in any area that may be
damaged by overflow from the main drain pan. In some
localities, local codes may require an secondary drain
pan for any horizontal installation.
The air handler is provided with ¾" NPT condensate drain
connections.
SLOPING THE DRAIN
Make sure the unit is sloped (similar to the slope shown in
figure 10) so that the drain pan will empty completely
without water standing in the pan.
THIS CORNER SHOULD BE
5/8" (+/− 1/8") HIGHER THAN DRAIN CORNER
DRAIN CORNER
THIS CORNER SHOULD BE
5/8" (+/− 1/8") HIGHER THAN
DRAIN CORNER
Figure 10. Sloping the Drain
INSTALL CONDENSATE DRAIN
1. Remove the appropriate drain knockouts. If
necessary, remove the indoor coil assembly from the
cabinet.
2. Connect primary drain line connection to the primary
drain pan connection. The primary drain connection is
flush with the bottom of the inside of the pan.
Secondary connection is raised above the bottom of
the inside of the pan.
NOTE When making drain fitting connections to the
drain pan, hand tighten the fitting and use a sealant.
Over−tightening the fittings can split connections on the
drain pan.
3. If the auxiliary drain line is to be used, remove the plug
and route the drain line so that water draining from the
outlet will be easily noticed by the homeowner.
4. After removal of drain pan plugs, check the drain port
to see if holes have been drilled. If not drilled, use a
19/32" bit to drill out the primary drain hole; use a 3/8"
drill bit for the secondary drain hole. Remove all drill
shavings.
5. Make sure 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 primary drain lines as close to the
unit as practical (see figure 11). 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 11). An extremely long horizontal run may require an
oversized drain line to eliminate air trapping.
NOTE Do not operate air handler without a drain trap.
The condensate drain is on the negative pressure side of
the blower; therefore, air being pulled through the
condensate line will prevent 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.
