Carrier 59SC2C Series Installation, Start-Up, Operating And Service And Maintenance Instructions page 19

Evaporator Coil
+
+
3/4" PVC
+
+
+
3/4
Condensing
Furnace
+
+
+
< +
< +
-
Blower
-
-
- -
-
+ = Positive pressure
< + = Pressure lower than areas with +
− = Negative pressure
Fig. 13 - - Example of Field Drain Attachment (Not Allowed)
Evaporator Coil
+ + +
+
Condensing
Furnace
+
+
+
< +
< +
-
Blower
-
-
- -
-
Open
standpipe
+
+
+
3/4" PVC
3/4
+
3/4
1/2" CPVC or larger*
+
< +
3/4
1/2
+
1/2
+
3/4
19
+ = Positive pressure
< + = Pressure lower than areas with +
+
+
− = Negative pressure
+
Blower creates positive pressure.
Positive pressure extends into coil
+ condensate drain (no trap).
< +
Furnace condensate does not flow
consistently when drain is at positive
+ pressure.
+
+
+
Evaporator Coil
+
+
+
+
3/4
Condensing
Furnace
+
+
+
< +
< +
-
Blower
-
-
- -
-
+ = Positive pressure
< + = Pressure lower than areas with +
− = Negative pressure
3/4" PVC
+
+
+
3/4" PVC
3/4
+
+
3/4
1/2" CPVC or larger*
+
+
3/4
< +
+
+
+
+
3/4
+
+
+ +
3/4
A14532