Thread: Water heater gas shut-off?

Is there a TP valve/Gas shut-off combination? Is it substandard? Correct me if I am wrong, but a shut-off valve, cap or plug should not be connected at the TP valve discharge. I've never run into this, can someone help me out? I would really appreciate it. The attached picture shows the fuel supply lines running in and out of what appears to be a TP valve/gas shut-off combination.

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Originally Posted by Edward Rodriguez

Is there a TP valve/Gas shut-off combination? Is it substandard? Correct me if I am wrong, but a shut-off valve, cap or plug should not be connected at the TP valve discharge. I've never run into this, can someone help me out? I would really appreciate it. The attached picture shows the fuel supply lines running in and out of what appears to be a TP valve/gas shut-off combination.

??

I'm totally lost.... you're mixing gas and water in the same pipes with your question?

From the picture things look pretty screwy but we need some clarification and/or more info to help you.

There is a valve that is designed to shut off the gas when overtemp/pressure is detected but your photo is not clear enough to tell much about it. Have a photo from further back to show where the lines go and a close-up of the valve?
Suggest you look at the Watts site to see what is available. LF210-5 Lead Free* Automatic Gas Shutoff Valves , Automatic Gas Shutoff Valve, Water Safety & Flow Control - Watts

Edward
As Jim pointed out, what it looks like you have is an automatic gas shutoff.
When the temperature gets to high the valve shuts off the gas, thereby keeping the temperature from rising any more.
What I don't see in the photo or on the Watts site, is a pressure relief valve.
The valve may be able to handle an over-temperature condition, but it is not able to handle an over-pressure condition.
A separate pressure valve will be needed for that.
Both temperature and pressure are required.

Watts 210 valve

Mike

Thanks fellas for all your help.

If you read through the Watts 210 installation instructions, you'll find that you still need a TPR valve and drain pipe. Plumbers here never install it until I note its absense and provide a copy of the Watts 210 installation instructions.

Originally Posted by Russel Ray

If you read through the Watts 210 installation instructions, you'll find that you still need a TPR valve and drain pipe. Plumbers here never install it until I note its absense and provide a copy of the Watts 210 installation instructions.

The Installation instructions call for a Pressure Relief Valve, not a Temperature Pressure Relief valve, Russ.

Edward;

Does your local AHJ allow galvanized gas pipe? Doesn't seam like a good idea to me.

Wow if you look close you will also notice they used standard t tape on the treads which is a no no. You can only use approved t tape which is yellow or approved pipe dope on gas lines.

Originally Posted by Bill Brooks

Wow if you look close you will also notice they used standard t tape on the treads which is a no no. You can only use approved t tape which is yellow or approved pipe dope on gas lines.

That is actually a fairly recent requirement -- Last 5 or 6 years or so.

This installation looks like it predates the requirement.

Originally Posted by Vern Heiler

Edward;

Does your local AHJ allow galvanized gas pipe? Doesn't seam like a good idea to me.

Galvanized pipe in gas piping is kind of a West Coast/UPC thing.

I use it when penetrating masonry (brick fireboxes, foundations, CMU block etc. . . ).

Steel is less susceptible to corrosion from lime than iron is.

Another big difference is in how the NG is sourced.

Most NG on the West Coast and into the Rockies comes from the North Slope in Alaska, which is very dry, while NG supplies in the Midwest and East Coast are often cracked from coal, which can leave a lot of moisture in the finished product.

It would be nice to see if this installation has a PRV mounted on top of the unit. It looks like the installation instructions show a condition with the pressure relief valve inline with the hot and gas shutoff at the side tap. (Figure 1.)

Why would only a PRV be installed when you could have the added safety of a TPR?

Originally Posted by Luc Lamarche

It would be nice to see if this installation has a PRV mounted on top of the unit. It looks like the installation instructions show a condition with the pressure relief valve inline with the hot and gas shutoff at the side tap. (Figure 1.)

Why would only a PRV be installed when you could have the added safety of a TPR?

I wonder if the reasoning behind this is because if you used a TPR (not just a PVR and Watts 210) and it (TPR) opened at a slightly lower temperature than the Watts 210, the 210 would be prevented from doing it's job and shutting off the gas.(?)

Originally Posted by Luc Lamarche

It would be nice to see if this installation has a PRV mounted on top of the unit. It looks like the installation instructions show a condition with the pressure relief valve inline with the hot and gas shutoff at the side tap. (Figure 1.)

Why would only a PRV be installed when you could have the added safety of a TPR?

It allows a PRV to be placed at a different location, so that it can drain by gravity. The Watts 210 is usually used where the water heater is landlocked, or too low to drain by gravity, in my experience, like in a basement area.

Originally Posted by Larry Morrison

I wonder if the reasoning behind this is because if you used a TPR (not just a PVR and Watts 210) and it (TPR) opened at a slightly lower temperature than the Watts 210, the 210 would be prevented from doing it's job and shutting off the gas.(?)

Exactly right.

I couldn't have said it better myself.