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What in the heck is this......

  • Thread starter Thread starter JayHawkInspector
  • Start date Start date
J

JayHawkInspector

Guest
I’m confused with this; I think they are calling this a gravity recirculation system, I don’t really know what it is maybe I can get some help on this one.

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I've seen recirc systems before, but they didn't look like that, they tied to the boiler drain, not the T & P.

I would think that besides violating the code, the manufacturers specs wouldn't allow it.
 
Jay Hawk,

Can't see all the piping; and, you never know what the manufacturer's will come up with next. However, the installation instructions are required to be on site, with the water heater.

The two different relief valves piped to each other appears to either be a very large pipe bomb; a do it yourself suicide kit; or the work of a very incompetent plumber.

PVC pipe is not allowed. The installation of the relief valve discharge pipe does not meet the requirements of 2006/2009 IRC; P2803.6.1.

You can find the installation instructions for A O Smith ProMax water heaters here;

http://www.hotwater.com/lit/im/r-gas.html

A side note:

These new "Direct Vent/Power Vent" water heaters are causing all kinds of problems;

http://www.consumeraffairs.com/homeowners/ao_smith_p4.html

They are suppose to get all their combustion air from the outside. What they are doing is causing people to have all kinds of problems;

Hope this helps,

Uncle Bob
 
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Is the valve in the tank a temperature relief valve and the valve in the line above the water heater a pressure relief valve? If so this system would work however as UB stated...no pvc allowed.
 
I am going to go out on a limb and assume the two T/Ps are tied together and then tee'ed to a floor drain (a bit of pvc is visible behind the riser to the CW T/P). If not, then this is a "Before" picture - please be sure to send the "After" picture, and let us know how far the water heater went.

I am going with stoopid, not criminally negligent. Perhaps the plumber thought a T/P in the cold line would be an acceptable alternate "device" to an expansion tank (it's not).

UB, I don't think this is a power vent unit. Note the draft diverter. Smith makes Category I "Pro Max" series as well as direct vent.
 
Not good! I would have to see the plans if there were any?

Never mind, fail!
 
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I agree the second T & P should be an expansion tank. No PVC pipe on T & P drain.

the theory of the gravity recirc is the copper return line is tied to the bottom drain of the tank. the cooler water in the return line will sink and the hot water at the top of the tank will move upward creating the "gravity loop". Really more a thermal issue and I ain't that smart too tell you if it works.

http://www.askthebuilder.com/147_Gravity_Hot_Water_Recirculating_Loops.shtml
 
Ok,

This is getting silly. You can't use the water heater relief valve to return water to the system! P E R I O D!

and,

You can't tie two relief valves together, causing them to terminate the piping with each other; WITH ANY KIND OF PIPE!

Good Grief;

P2803.6.1 Requirements for discharge pipe. The discharge piping serving a pressure-relief valve, temperature relief valve or combination valve SHALL:

4. Serve A SINGLE RELIEF DEVICE and SHALL NOT CONNECT TO PIPING SERVING ANY OTHER RELIEF DEVICE or equipment.

8. (SHALL!) Not be trapped.

9. (SHALL!) Be installed to flow by gravity.

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

Now, Look at the picture.

For crying out loud!

Uncle Bob
 
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* * *



No purple primer either... per Section P3003.9.2 & P3003.14.2 in the `06 IRC.



* * *
 
While it appears this is not code compliant, I believe that licensed professionals - plumbers and electricians, have the knowledge and right to combine off the shelf items to produce custom items and use those in construction.

The water heater tank is simply part of another larger custom item that includes water heating and has a second T&P in case the primary one should fail to open.
 
Many times; while inspecting in the field; I get the question of "WHY?"; conserning code requirements; and that is one of the reasons I enjoy researching the answers.

Being a licensed Plumber or Electrician; means you passed a test; perhaps several years ago. It doesn't mean that you "still" know what you are doing;

http://www.kpho.com/video/17195284/index.html

If this water heater had been gas; there would have also, most likely been a fire.

It's the same for Inspectors; many of which don't keep up their certifications; and more today don't need them; with State licensing. It's not enough to know the codes; we need to know why, and be able to explain it to others.

With large retail outlets; like Lowes and Home Depot; encouraging homeowners to "Do it yourself"; and, State laws exempting homeowners from having to hire a "professional"; there will be more damage to homes and lives.

Uncle Bob
 
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PA really has no plumbing, contractor or electrician licensing. I see that kind of thing EVERY day. crazy is the word.
 
I watch mythbusters a while back and they built a small structure of typacal wood frame construction, installed a electric water heater, and defeated the safety controls and plugged the T & P. Blew they structure to pieces when it went, I cant rmember how high it went, but they really couldn't track it with the camera. Pretty wild stuff.
 
i saw that also i think you can see it here or u-tube. work will not allow me to access it but i think that is it below

metacafe.com/watch/yt-JmJoyuUJj2Q/mythbusters_water_heater
 
And you had that link memorized?????? WOW!!!!

Oh...yes that is the correct link.
 
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