Incorrect Water Heater Discharge Installation?

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InjuredReserve

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I have a new construction house that was built in a group of 4 by the same builders - same construction, same floorplan. We have noticed some small inconsistencies, but this week I noticed one with my water heater setup and the way the emergency discharge is installed:
upload_2019-10-23_8-6-9.png
upload_2019-10-23_8-6-27.png


The problem is that I can't find any evidence that this actually goes anywhere. There is nothing going down into the crawl space and nothing on the exterior of the house. Both of my neighbors with the same floorplan have this:
upload_2019-10-23_8-6-42.png

Is this an issue that needs to be addressed?

There is also a separate run of pvc with uncapped ends that I'm unsure of their purpose:
upload_2019-10-23_8-10-7.png

upload_2019-10-23_8-10-43.png

Thank you.
 

Rossando

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That discharge pipe from the pan should be piped to the outside of the house or close to a drain.
 

johnjh2o

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With it piped to the crawl space there is no way you would be aware there is a problem with the heater.
 

Jeff Handy

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Give more info about the pvc pipes, their source, their size, and where they are ending up.

You can put the sensor for a water alarm in the pan under your water heater.
Or at the outlet of any pipes that have been installed to carry away water in the event of a leak.
 

Mikey

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With it piped to the crawl space there is no way you would be aware there is a problem with the heater.
The code requires the discharge to be through an air gap that is (arguably -- I argue for it) at the water heater, so you can see it drip/flow directly. There's a long discussion about this elsewhere in the forum, and a more general article about the TPR valve at http://www.ashireporter.org/HomeInspection/Articles/The-Temperature-Pressure-Relief-Valve/1568. The full code section is:

504.6 Requirements for discharge piping.
The discharge piping serving a pressure relief valve, temperature relief valve or combination thereof 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
    serving 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 so as to flow by gravity.
  10. Not terminate more than 6 inches (152 mm) above the
    floor or waste receptor.
  11. Not have a threaded connection at the end of such piping
 

johnjh2o

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From what I'm seeing it's not connected to a waste line it's just dumping into the crawl space.
 

Diehard

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I doubt a crawl space meets the requirement of the code that says. "Discharge to a termination point that is readily observable
by the building occupants."

The purpose of an air gap is primarily to prevent any chance of cross connection/backflow into a portable water system. So dropping into that PVC pipe is not acceptable. It's an air break and is subject to drawing back anything that pipe ends up getting filled with, including whatever may have been sitting in that pan.

The pan could serve as an indirect waste receptor with the P&T relief pipe terminating at least 6" above the rim.

Then it would meet the readily observable requirement regardless of it dumps in the crawl space or elsewhere.
 

Mikey

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The purpose of an air gap is primarily to prevent any chance of cross connection/backflow into a portable water system.
I always thought the primary purpose was to allow it to be readily observed. These things do fail, and some (but not all) folks recommend giving the release a little tap now and then to a) see that it does flow, and b) see that it stops. Testing or not, looking at the outlet regularly may alert you to future problems.
 

Diehard

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I guess I was using the word Primary as meaning the most important reason.
I suppose that may be a matter of opinion.
I agree with your good reasons to be readily observed.
I would put prevention of potential contamination of potable water above an alert to a problem.

I was a NEWWA Certified Cross Connection Control Surveyor while working for an environmental engineering firm that designed water and wastewater treatment plants. So my brain tends to focus more on that subject.

When you mentioned, "and some (but not all) folks recommend giving the release a little tap now and then", for some reason frodo immediately came to mind.
 

Mikey

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I find that giving my release three good taps results in much less annoying dripping.
Yeah, I give mine a whack whenever I change the air handler filter (right next to the WH). I figure it clears out any crud that's accumulating; the "don't whack" side figures it might allow crud to move from "accumulating" to "blocking". Different strokes...
 

Jeff Handy

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A little saying I heard back in grade school was,
“No matter how you squirm and dance,
The last drops always fall in your pants”
 
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