Water heater TPR extension question

[Anthony A. Cassady]

Can the TPR extension for the water heater have elbows routing it to a drain and if so is there limit on how many? The water heater I inspected today had 5 elbow 90 degree turns before draining into the floor drain....thanks ahead of time

[Chuck Evans]

Yes, I know of no limit to the number. It must gravity drain and not be restricted.

[James H. Bushart]

Depending upon the direction of the turns....for the water must be able to flow by gravity....there are no limits to numbers in the IRC or UPC, but there must be an air gap between the end of the pipe and top of the drain to ensure that it can be viewed and will not be blocked.

[Kenneth E. Sitzes]

2006 INTERNATIONAL RESIDENTIAL CODE@

P2803.6.1 Requirements for discharge pipe.

The discharge piping sewing a pressure-relief valve, temperaturerelief valve or combination valve shall:

1. Not be directly connected to the drainage system.

2. Discharge through an air gap located in the same room as the water heater.

3. Not be smaller than the diameter of the outlet of the valve served and shall discharge full size to the air gap.

4. Serve a single relief device and shall not connect to piping sewing any other relief device or equipment.

5. Discharge to the floor, to an indirect waste receptor or to the outdoors. Where discharging to the outdoors in areas subject to freezing, discharge piping shall be first piped to an indirect waste receptor through an air gap located in a conditioned area.

6. Discharge in a manner that does not cause personal injury or structural damage.

7. Discharge to a termination point that is readily observable by the building occupants.

8. Not be trapped.

9. Be installed to flow by gravity.

10. Not terminate more than 6 inches (152 mm) above the floor or waste receptor.

1 1. Not have a threaded connection at the end of the piping.

12. Not have valves or tee fittings.


13. Be constructed of those materials listed in Section P2904.5 or materials tested, rated and approved for such use in accordance with ASME A1 12.4.1.

[David E. Helm]

While there don't seem to be rules regarding the number of elbows, as a practical matter four 90s seems to be a good indicater of the ability to flow unrestricted.

[Mark Nicholet]

It shouldn't be reduced and or have threads providing opportunity to cap.