Shutoff Valve in Hot Water Line of Water Heater

[jadnashua]

Got a car without an emergency brake lately?

Actually, the new car I just bought uses a computer driven hydraulic system for the parking brake...there is no direct mechanical lever or pedal to mechanically operate the brakes. If the engine is running, it works on all 4 wheels, if it's not, it only works on the rear wheels. You pull the little switch up to activate, and push it down to turn it off.

As we've gone over multiple times, the code approved method is an expansion tank along with the factory T&P valve. If doing more makes you feel better, go for it, but millions of people don't do more and their tanks haven't blown up, nor do I expect that they will.

[ballvalve]

Wheel chocks are required by law in many places for trucks because they are mechanisms in PLAIN SIGHT that do not fail.

And all my tractors and excavators have hydraulic acculumulators, seem to NEVER break or leak, and within a few seconds lock up all drive mechanisms when the engine is killed. As soon as you turn off a 100,000 pound excavator, you have nothing to do but go home, no levers to pull. Great system.

Very handy on the edge of a cliff when the engine dies and braking power ends. Might not work so well on a pickup at 80 MPH on the freeway.

A hydraulic accumulator on autos, with brains, would be a huge safety factor for braking and parking.

Funny how a backup relief valve disturbs everyone. But all those stupid backflow valves that we lived without for 150 years are gods new standard without question. How many of you got sick from reverse flow water? Better to regulate chickens in the market for bacteria.

[Redwood]

Funny how a backup relief valve disturbs everyone. But all those stupid backflow valves that we lived without for 150 years are gods new standard without question.

Because you propose it instead of a thermal expansion tank which is about the equivalent of us saying strip the brakes off your truck because they might fail and use "Fail Safe Wheel Chocks" instead....

The fact is your relief valves can and do fail quite often and plumbed to a drain and in a failed or, operational state could conceivably run full flow unnoticed until a well goes dry or, you have a heart attack when you open your water bill.

So jump off your engineer soap box and realize the data and logic you are applying to your brilliant solution is flawed badly.

That is why we repeat ourselves every time you mention this....

We will repeat it as often as you do, because bad advice does need to be exposed as such.

[ballvalve]

Sure expansion tanks help, when NEEDED, but they have the same pressure rating as the heater body, so blowing the internal bag is not back up like another pressure valve. You can do another myth busters video with a expansion tank in the circuit, and the simple question is which one blows first.

Unless you have 2 shut off valves on the water heater and a absent relief valve, the value of the exploding water heater videos is the same as a video showing what happens when you build your charcoal barbeque fire right under the gas tank of your motor home.

[Redwood]

Okay... Let me get this straight now...

If someone turns off the two valves on the inlet and outlet of the water heater... (Even though us plumbers don't put one on the outlet)

and...

If the T&P Valve fails..... which is easily tested and should be regularly.....

and...

If the Thermostat fails in a manner which causes heating continuously 50-50 chance....

and....

If the TCO (Thermal Cut Off) fails....

Oh Boy Mr Engineer... Just how much redundancy do you want anyway?

By your theory we've got your dump truck parked:

The emergency brake is set...

and

The engine is off and in lowest gear...

and

the wheel chocks are in place

and

the truck is on level ground....

All we can do now is take your silly azz little ball valve and throw it at the window breaking it....

Come on Ball valve grow some grey matter will ya?

[ballvalve]

Everyone must be bored around here.

My point was that the exploding water heater videos are fun, but almost irrelevant. As you well point out with all the other devices to be bypassed.

Leave out the hot shut off, and now you have lots of pipes and hoses that can become your pressure relief valve.

As to grey matter, dump trucks do not have nitrogen filled liquid hydraulic accumulators for the e-brake. And the dump truck driver with the most of it actually uses his wheel chocks.

In case you missed the POINT - expansion tanks provide no help with a run-away [tampered with] water heater.

[Redwood]

Everyone must be bored around here.

No, We are just tired of you the "Unknowing" spewing your lack of wisdom on this subject and determined to rebut the bad advice you consistently spew...

We have tried to educate you on the subject but due to a lack of absorbency your grey matter repels knowledge...

This is a common occurrence in some people in your chosen field. Most continue to educate themselves all through life and become very good in the field. Others blindly decide at some point that they know everything and at that point cease to have any value.

In case you missed the POINT - expansion tanks provide no help with a run-away [tampered with] water heater.

And your ball valve with a relief does?

If you will note at the product link you provided it states...

"It is for applications that require a means to shut off the water supply to the water heater and for providing protection from excess water pressure caused by thermal expansion."

Your assumption that it provides protection with a runaway water heater is completely out to lunch.

A properly sized T&P Valve will provide that protection. In looking at the specifications for the Watts 100XL T&P Valve you will not the following lines of information that do not appear on the product you recommend...

A.S.M.E Rated*, CSA Listed. Self-closing T&P Relief Valves
for Water Heaters up to 105,000 BTU/Hr.
The combined 2 in 1 T&P relief valve provides the least expensive and proven means for protection against both excessive
temperature and pressure emergency conditions.
Provides fully automatic temperature and pressure relief protection for hot water storage tanks and heaters up to 105,000 BTU/HR.

Each water heater and hot water storage tank shall be
equipped with a CSA and A.S.M.E. Rated* automatic temperature and pressure relief valve to protect the heater from excessive pressure and temperature. The device shall be ANSI Z21.22 certified. The BTU discharge capacity of the device
shall be in excess of the BTU input rating of the heater.

Now I'm not a General Engineering Contractor so I don't profess too have knowledge about digging irrigation ditches, land leveling, installing driveways, and ditch digging... Frankly I don't want that knowledge... I'll bow to your excellence or, hire some undocumented day laborers to do the work...

I'm a plumber! That is my area of expertise...
The engineers at Watts are a slightly different type of engineer than you are...
They have expertise in the safety controls needed on a water heater. So me the plumber having an awareness that you lack have decided that...

I will have a safety device that is CSA and A.S.M.E. Rated, ANSI Z21.22 certified, With a BTU discharge capacity in excess of the BTU input rating of the heater...

Now go dig a ditch or, something....

[Hillbilly Man]

Now go dig a ditch or, something....

Hot Dang Redwood!
Wat is it wit alla these engineeers that wanna think they knows mor bout plummin than Redwood.
They seems ta have no end to the line of em comin ta git ther noze bleedin.

[ballvalve]

The unknowing with repellant soft grey matter dont know the meaning of redundency and rely on granpas valves rather than the new choices in conjunction with the valve that comes installed on the heater.

Must be bored not having Ian to kick around lately. Glad to be of service.

[Redwood]

You give yourself way more credit than you are due...