Condensate from air washers, air-cooling coils, condensing appliances, and the overflow
from evaporative coolers and similar water-supplied equipment
or similar air-conditioning equipment shall be
collected and discharged to an approved plumbing fixture
or disposal area. Where discharged into the drainage
system, equipment shall drain by means of an indirect waste
pipe. The waste pipe shall have a slope of not less than 1/8
inch per foot (10.4 mm/m) or 1 percent slope and shall be
of approved corrosion-resistant material not smaller than
the outlet size in accordance with Section 814.3 or Section
814.4 for air-cooling coils or condensing appliances,
respectively. Condensate or wastewater shall not drain over
a public way.
Where approved by the Authority Having Jurisdiction, condensate pumps shall
be installed in accordance with the manufacturer's
installation instructions. Pump discharge shall rise
vertically to a point where it is possible to connect to a
gravity condensate drain and discharged to an approved
disposal point. Each condensing unit shall be provided
with a separate sump and interlocked with the equipment
to prevent the equipment from operating during a
failure. Separate pumps shall be permitted to connect to
a single gravity indirect waste where equipped with
check valves and approved by the Authority Having
Jurisdiction.
Where an equipment or appliance
is installed in a space where damage is capable of
resulting from condensate overflow, other than damage to
replaceable lay-in ceiling tiles, a drain line shall be
provided and shall be drained in accordance with Section
814.1. An additional protection method for condensate
overflow shall be provided in accordance with one of the
following:
- A water level detecting device that will shut off the equipment or appliance in the event the primary drain is blocked.
- An additional watertight pan of corrosion-resistant material, with a separate drain line, installed beneath the cooling coil, unit, or the appliance to catch the overflow condensate due to a clogged primary condensate drain.
- An additional drain line at a level that is higher than the primary drain line connection of the drain pan.
- An additional watertight pan of corrosion-resistant material with a water level detection device installed beneath the cooling coil, unit, or the appliance to catch the overflow condensate due to a clogged primary condensate drain and to shut off the equipment. The additional pan or the additional drain line connection shall be provided with a drain pipe of not less than 3/4 of an inch (20 mm) nominal pipe size, discharging at a point that is readily observed.
Where insulation or appurtenances are installed where damage is
capable of resulting from a condensate drain pan overfill,
such installations shall occur above the rim of the
drain pan with supports. Where the supports are in
contact with the condensate waste, the supports shall be
of approved corrosion-resistant material.
Condensate waste pipes from air-cooling coils shall be
sized in accordance with the equipment capacity as specified
in Table 814.3. The material of the piping shall comply
with the pressure and temperature rating of the appliance or
equipment, and shall be approved for use with the liquid
being discharged.
For SI units: 1 ton of refrigerant = 3.52 kW, 1 inch = 25 mm
The size of condensate waste pipes is for one unit or a combination of units, or as recommended by the manufacturer. The capacity of waste pipes assumes a 1/8 inch per foot (10.4 mm/m) or 1 percent slope, with the pipe running three-quarters full at the following pipe conditions:
For SI units: °C = (°F-32)/1.8
Condensate drain sizing for other slopes or other conditions shall be approved by the Authority Having Jurisdiction.
Air-conditioning waste pipes shall be constructed of materials specified in Chapter 7.
| EQUIPMENT CAPACITY IN TONS OF REFRIGERATION |
MINIMUM CONDENSATE PIPE DIAMETER (inches) |
|---|---|
| Up to 20 | 3/4 |
| 21 - 40 | 1 |
| 41 - 90 | 11/4 |
| 91 - 125 | 11/2 |
| 126 - 250 | 2 |
The size of condensate waste pipes is for one unit or a combination of units, or as recommended by the manufacturer. The capacity of waste pipes assumes a 1/8 inch per foot (10.4 mm/m) or 1 percent slope, with the pipe running three-quarters full at the following pipe conditions:
| Outside Air - 20% | Room Air - 80% | ||||
|---|---|---|---|---|---|
| DB | WB | DB | WB | ||
| 90°F | 73°F | 75°F | 62.5°F | ||
Condensate drain sizing for other slopes or other conditions shall be approved by the Authority Having Jurisdiction.
Air-conditioning waste pipes shall be constructed of materials specified in Chapter 7.
Condensate drain lines shall be
configured or provided with a cleanout to permit the
clearing of blockages and for maintenance without
requiring the drain line to be cut.
Condensate drain
lines from individual condensing appliances shall be sized
as required by the manufacturer's instructions. Condensate
drain lines serving more than one appliance shall be
approved by the Authority Having Jurisdiction prior to installation.
Air-conditioning condensate waste pipes shall connect indirectly, except where permitted
in Section 814.6, to the drainage system through an air gap
or air break to trapped and vented receptors, dry wells,
leach pits, or the tailpiece of plumbing fixtures. A condensate
drain shall be trapped in accordance with the appliance
manufacturer's instructions or as approved.
Where the condensate waste from air-conditioning coils
discharges by direct connection to a lavatory tailpiece or to
an approved accessible inlet on a bathtub overflow, the
connection shall be located in the area controlled by the
same person controlling the air-conditioned space.
Female plastic screwed fittings shall
be used with plastic male fittings and plastic threads.