UpCodes logo
Jump To Full Code Chapter
Condensate drain systems shall be provided for equipment and appliances containing evaporators or cooling coils. Condensate drain systems shall be designed, constructed and installed in accordance with Sections 314.2.1 through 314.2.5.
[M] 314.2.1 Condensate Disposal
Condensate from all cooling coils and evaporators shall be conveyed from the drain pan outlet to an approved place of disposal. Such piping shall maintain a horizontal slope in the direction of discharge of not less than one-eighth unit vertical in 12 units horizontal (1-percent slope). Condensate shall not discharge into a street, alley or other areas so as to cause a nuisance.
[M] 314.2.1.1 Condensate Discharge
Condensate drains shall not directly connect to any plumbing drain, waste or vent pipe. Condensate drains shall not discharge into a plumbing fixture other than a floor sink, floor drain, trench drain, mop sink, hub drain, standpipe, utility sink or laundry sink. Condensate drain connections to a lavatory wye branch tailpiece or to a bathtub overflow pipe shall not be considered as discharging to a plumbing fixture. Except where discharging to grade outdoors, the point of discharge of condensate drains shall be located within the same occupancy, tenant space or dwelling unit as the source of the condensate.
[M] 314.2.2 Drain Pipe Materials and Sizes
Components of the condensate disposal system shall be ABS, cast-iron, copper and copper-alloy, CPVC, cross-linked polyethylene, galvanized steel, PE-RT, polyethylene, polypropylene, PVC, or PVDF pipe or tubing. Components shall be selected for the pressure and temperature rating of the installation. Joints and connections shall be made in accordance with the applicable provisions of Chapter 7 relative to the material type. Condensate waste and drain line size shall be not less than 3/4-inch (19.1 mm) pipe size and shall not decrease in size from the drain pan connection to the place of condensate disposal. Where the drain pipes from more than one unit are manifolded together for condensate drainage, the pipe or tubing shall be sized in accordance with Table 314.2.2.
TABLE 314.2.2
[M] TABLE 314.2.2
CONDENSATE DRAIN SIZING
EQUIPMENT CAPACITY MINIMUM CONDENSATE PIPE DIAMETER (inch)
Up to 20 tons of refrigeration 3/4 inch
Over 20 tons to 40 tons of refrigeration 1 inch
Over 40 tons to 90 tons of refrigeration 11/4 inches
Over 90 tons to 125 tons of refrigeration 11/2 inches
Over 125 tons to 250 tons of refrigeration 2 inches
For SI: 1 inch = 25.4 mm, 1 ton of capacity = 3.517 kW.
[M] 314.2.3 Auxiliary and Secondary Drain Systems
In addition to the requirements of Section 314.2.1, where damage to any building components could occur as a result of overflow from the equipment primary condensate removal system, one of the following auxiliary protection methods shall be provided for each cooling coil or fuel-fired appliance that produces condensate:
  1. An auxiliary drain pan with a separate drain shall be provided under the coils on which condensation will occur. The auxiliary pan drain shall discharge to a conspicuous point of disposal to alert occupants in the event of a stoppage of the primary drain. The pan shall have a depth of not less than 11/2 inches (38 mm), shall be not less than 3 inches (76 mm) larger than the unit or the coil dimensions in width and length, and shall be constructed of corrosion-resistant material. Galvanized sheet metal pans shall have a thickness of not less than 0.0236-inch (0.6010 mm) (No. 24 gage) galvanized sheet metal. Nonmetallic pans shall have a thickness of not less than 0.0625 inch (1.6 mm).
  2. A separate overflow drain line shall be connected to the drain pan provided with the equipment. Such overflow drain shall discharge to a conspicuous point of disposal to alert occupants in the event of a stoppage of the primary drain. The overflow drain line shall connect to the drain pan at a higher level than the primary drain connection.
  3. An auxiliary drain pan without a separate drain line shall be provided under the coils on which condensate will occur. Such pan shall be equipped with a water-level detection device conforming to UL 508 that will shut off the equipment served prior to overflow of the pan. The auxiliary drain pan shall be constructed in accordance with Item 1 of this section.
  4. A water-level detection device conforming to UL 508 shall be provided that will shut off the equipment served in the event that the primary drain is blocked. The device shall be installed in the primary drain line, the overflow drain line or in the equipment-supplied drain pan, located at a point higher than the primary drain line connection and below the overflow rim of such pan.
Exception: Fuel-fired appliances that automatically shut down operation in the event of a stoppage in the condensate drainage system.
[M] 314.2.3.1 Water-Level Monitoring Devices
On down-flow units and all other coils that do not have a secondary drain or provisions to install a secondary or auxiliary drain pan, a water-level monitoring device shall be installed inside the primary drain pan. This device shall shut off the equipment served in the event that the primary drain becomes restricted. Devices installed in the drain line shall not be permitted.
[M] 314.2.3.2 Appliance, Equipment and Insulation in Pans
Where appliances, equipment or insulation are subject to water damage when auxiliary drain pans fill such portions of the appliances, equipment and insulation shall be installed above the flood level rim of the pan. Supports located inside of the pan to support the appliance or equipment shall be water resistant and approved.
[M] 314.2.3.3 Identification
The termination of concealed condensate piping shall be marked to indicate whether the piping is connected to the primary or secondary drain.
[M] 314.2.4 Traps
Condensate drains shall be trapped as required by the equipment or appliance manufacturer.
[M] 314.2.4.1 Ductless Mini-Split System Traps
Ductless mini-split equipment that produces condensation shall be provided with an in-line check valve located in the drain line or a trap.
[M] 314.2.5 Drain Line Maintenance
Condensate drain lines shall be configured to permit the clearing of blockages and performance of maintenance without requiring the drain line to be cut.

Related Code Sections

307.1 General Regulations, Evaporators and Cooling Coils
Condensate drainage systems shall be provided for equipment and appliances containing evaporators and cooling coils in accordance ...
307.1 General Regulations, Evaporators and Cooling Coils
Condensate drainage systems shall be provided for equipment and appliances containing evaporators and cooling coils in accordance ...
307.1 General Regulations, Evaporators and Cooling Coils
Condensate drainage systems shall be provided for equipment and appliances containing evaporators and cooling coils in accordance ...
307.2 General Regulations, Evaporators and Cooling Coils
Condensate drain systems shall be provided for equipment and appliances containing evaporators or cooling coils. Condensate drain systems shall ...
307.2 General Regulations, Evaporators and Cooling Coils
Condensate drain systems shall be provided for equipment and appliances containing evaporators or cooling coils. Condensate drain systems shall ...