507621-01
Issue 1720
Page 8 of 23
Condensate Drain
The air handler is provided with ¾” NPT condensate drain connections.
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
ABOVE
FINISHED
SPACE?
SECONDARY (OVERFLOW) DRAIN LINE
ALWAYS RUN A SECONDARY (OVERFLOW) DRAIN LINE. IF NOT
POSSIBLE, INSTALL LOW VOLTAGE OVERFLOW SWITCH KIT.
WIRE KIT TO SHUT DOWN COMPRESSOR PER INSTRUCTIONS.
NO
YES
PART #
X3169
CLEAN OUT
VENT
PRESS IN
(DO NOT GLUE)
VENT MUST EXTEND
ABOVE HEIGHT OF
COIL DRAIN PAN BY
TWO INCHES (51MM)
1” X 3/4” X 3/4”
REDUCING
TEE WITH
PLUG
P-TRAP
1
#
49P66,
J-TRAP # 91P90
OR ANY PVC SCH
40 P- OR J-TRAP 3/4”
AIR HANDLER DRAIN PAN
WHEN A COIL IS LOCATED ABOVE A FINISHED
SPACE, A 3/4” (19.1MM) SECONDARY DRAIN LINE
MUST BE:
●
CONNECTED TO SECONDARY DRAIN PAN
OR
●
CONNECTED TO THE SECONDARY
(OVERFLOW) DRAIN OUTLET OF THE AIR
HANDLER DRAIN PAN.
TRAP MUST BE DEEP ENOUGH TO OFFSET MAXIMUM STATIC DIFFERENCES — GENERALLY,
TWO INCHES (51MM).
DRAIN LINE SHOULD
SLOPE A MINIMUM OF
ONE INCH PER 10 FEET
(25MM PER 3 METERS)
NOTE
-
WHEN AN AIR HANDLER IS LOCATED
ABOVE A FINISHED SPACE, THE SECONDARY
DRAIN PAN MUST HAVE A LARGER FOOTPRINT
THAN THE AIR HANDLER.
MAIN DRAIN
TO APPROVED
DRAIN
FOR NEGATIVE PRESSURE COILS (BLOWER
AFTER COIL), A TRAP IS REQUIRED ON THE
MAIN DRAIN LINE CONNECTED TO COIL.
REQUIREMENTS ON SECONDARY DRAINS.
USE TWO-PART 3/4” FEMALE SLIP INLET AND MALE ADAPTER
WHEN OBSTRUCTIONS PREVENT DIRECT THREADING OF
OVERFLOW SWITCH.
SECONDARY
DRAIN PAN
2”
(51MM)
TRAP DEPTH
1
P-TRAP 49P66 REQUIRES A LARGER INSTALLATION SPACE THAN THE J-TRAP 91P90.
2
PIPE NIPPLE PROVIDED IN BAG ASSEMBLY - SCH 80, 3/4” I. D. X 5” - 34K7401 (1): CUT THE PIPE
IN HALF AND USE IT TO ROUTE THE MAIN DRAIN.
SEE LOCAL CODES FOR TRAP
Figure 10. Typical Main and Overflow Drain
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 a
secondary drain pan for any horizontal installation.
IMPORTANT
