HVAC Condensate Drain Requirements

[jvdm]

I am concerned that the condensate pipes from my HVAC unit are not installed to code. I live in Washington, DC.

The HVAC unit is in a closet off the kitchen in a second floor condo. Condensate from the furnace and air conditioner currently drain through a 1 inch pipe to an ejector pump on the closet floor. The pump pumps the condensate into a ½ inch rubber tube that runs up about 10 inches, through a hole in the wall, and into a pantry closet. It runs along the back wall of that closet (outside the wall, with no slope), and into the wall on the other side of the closet. I think it then connects to a sink drain, but I can’t be sure.

The pump is not sitting in a catch pan and it does not have an automatic shut off. If the pump failed, the condensate would leak into the back of the HVAC closet and damage the downstairs condo.

I am concerned this is not to code in Washington, DC because Section 314 of the Plumbing Code and Section 307 of the Mechanical Code require drain pipes that (1) are least the size of the connection on the appliance (i.e. 1 inch), (2) have a 1 percent slope to an approved piping fixture, and (3) do not decrease in size before they reach the piping fixture.

The pump and tube running out of the pump appear to violate these requirements because they (1) decreases the pipe diameter from 1 inch to ½ inch and (2) disrupt the 1 percent slope requirement.

The plumbing and mechanical codes also require that the condensate be discharged “in accordance with the manufacturer’s installation instructions.” The instructions provide several options for condensate disposal, but none of the options show a pump.

Is my current configuration a code violation in Washington, DC? If not, what part of the code allows for my current configuration? Should I try to have the pump replaced with a 1 inch pipe that slopes down to the sink drain? What other issues should I be concerned about?

 

[CT18]

Make sure you are looking at a pumped system. The slope will generally pertain to a gravity system. In my location you can run the 1" to a condo pump and then 1/2" tubing pumped to a sink drain. Most of the pumped system is strapped to the water piping in the basement.

 

[jvdm]

CT18, thank you for replying to my post. Do you happen to know where the requirements for a pumped system are written in the code? I know some states, like North Carolina, have specific requirements for pumps in Section 307.2.1, but I can't find anything similar in the DC Codes. If you, or anyone else, can point me to where any applicable requirements for pumped systems are written in the code, I would definitely appreciate the help.

 

[skelly716]

I'm in CA and in the CMC there is a section in chapter 3 (310.2) that reads additional protection from leakage or overflow shall be provided.

(1) A water level detecting device that will shut off the
equipment or appliance in the event the primary drain is
blocked.
(2) 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.
(3) An additional drain line at a level that is higher than the
primary drain line connection of the drain pan.
(4) 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 % of
an inch (20 rom) nominal pipe size, discharging at a point that
is readily observed.