After removal of drain pan plug(s), check drain hole(s)
to verify that drain opening is fully open and free of any
debris. Also check to make sure that no debris has
fallen into the drain pan during installation that may plug
up the drain opening.
Connect the main drain and route downward to drain line
or sump. Do not connect drain to a closed waste system.
be connected and routed to a
The following best practices are recommended to ensure
better condensate removal:
•
than both drain connections at drain pan.
•
homeowner will notice drainage.
•
vented and a trap installed. Refer to local codes.
Proper air volume MUST be provided over the evaporator
coil. To ensure that the static pressure is within the proper
range, take a draft gauge reading as follows:
Access panel must be removed before drilling air test
holes.
ABOVE
FINISHED
SPACE?
OVERFLOW DRAIN LINE
ALWAYS RUN AN OVERFLOW DRAIN LINE. IF NOT POSSIBLE TO
ROUTE OVERFLOW DRAIN LINE, INSTALL LOW VOLTAGE
OVERFLOW SWITCH KIT. WIRE KIT TO SHUT DOWN
COMPRESSOR PER INSTRUCTIONS.
NO
YES
CLEAN OUT
VENT
PRESS IN
(DO NOT GLUE)
VENT MUST EXTEND
ABOVE HEIGHT OF
COIL DRAIN PAN BY
TWO INCHES (51 MM)
1” X 3/4” X 3/4”
REDUCING
TEE WITH
PLUG
PVC SCH 40 P- OR
J-TRAP 3/4”
OVERFLOW
DRAIN
OPTIONAL
SAFETY
PAN
FURNACE DRAIN PAN
WHEN A COIL IS LOCATED ABOVE A FINISHED SPACE, A 3/4” (19.1 MM) SECONDARY DRAIN
LINE MUST BE:
CONNECTED TO SECONDARY DRAIN PAN
OR
CONNECTED TO THE OVERFLOW DRAIN OUTLET OF THE FURNACE DRAIN PAN.
TRAPS MUST BE DEEP ENOUGH TO OFFSET MAXIMUM STATIC DIFFERENCES —
GENERALLY, TWO INCHES (51 MM).
DRAIN LINE SHOULD
SLOPE A MINIMUM OF
ONE INCH PER 10
FEET (25 MM PER 3
METERS)
NOTE
— WHEN A FURNACE IS LOCATED ABOVE A FINISHED SPACE, THE SECONDARY DRAIN
PAN MUST HAVE A LARGER FOOTPRINT THAN THE FURNACE .
MAIN
DRAIN
TO APPROVED
DRAIN
FOR NEGATIVE PRESSURE COILS (BLOWER
AFTER COIL) TRAPS ARE REQUIRED ON ALL
DRAIN LINES CONNECTED TO COIL.
COMPACT OVERFLOW SWITCH WITH 3/4” FEMALE SLIP INLET
AND MALE ADAPTER, TWO-PART DESIGN FOR USE WHERE
OBSTRUCTIONS PREVENT DIRECT THREADING
SECONDARY
DRAIN PAN
2”
(51 MM)
TRAP DEPTH
Page 9
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