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CLCH-SVX03C-EN
Coil Piping and Connections
Drain Pan Trapping
WARNING
No Step Surface!
Do not walk on the sheet metal drain pan. Walking on the drain pan could cause the supporting
metal to collapse. Failure of the drain pan could result in death or serious injury.
NOTICE
Water Damage!
When more than one module has a drain pain, trap each module individually. Connecting all
drains to a common line with only one trap can result in condensate retention and possible
water damage to the air handler or adjoining space.
Threaded condensate drain connections are provided on only one side of the coil module. Pitch the
connection lines horizontal or downward toward an open drain. Trane recommends installing a
plug to facilitate cleaning of the trap.
The drain connection size is 1-inch NPT (National Pipe Thread) external for unit sizes 3 to 30;
1 1/4-inch NPT external for unit sizes 35, 40, 50, and 57; and 1 1/2-inch internal threads on sizes 66,
80, 100, and 120.
Figure 46
illustrates the proper trapping, piping, and operation of the trap for negative pressure
modules. Use the formula under the figure to determine the correct minimum depth for the
condensate trap.
Figure 47
illustrates the proper trapping, piping, and operation of the trap for positive pressure
modules.
Note:
Positive pressure traps require a different design than negative pressure traps.
If a module has a drain pan for cleaning purposes only, it does not need a trap; however, a cap or
shutoff valve should be installed on the drain connection. Only modules handling condensate, such
as a cooling coil module or moisture eliminator module, require a trap.