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(10-03-2017, 07:09 PM)geek2me Wrote: No disagreement - the point that you got wrong is the claim that the valve will work correctly with anything other than water.
Simple experiment to prove the point. Fill two balloons, one with water and one with air, to the same size. Both have the same pressure, which is shown by them being the same size. Poke both balloons with a pin - the water-filled balloon will collapse, the air-filled balloon will explode.
Air is also a good thermal insulator, which is why the temperature part of the valve will not work correctly with air, for example.
Comparing the failure mode of a latex balloon to a steel tank is about the most rediculous thing I have read here in a long time.
Put a piece of duct tape on your balloons and repeat your test by poking the pin through the tape and let us know the results...
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(10-03-2017, 07:05 PM)geek2me Wrote: Well, you are certainly entitled to your opinions, I'm just sharing the facts so people can make informed choices.
Not sure what you misunderstood about my post, as your link shows the facts I shared regarding T/P valves are correct ("Protects water heaters from excessive water temperatures and pressure"). Again, the key point is they are designed for water pressure and temperature and won't work correctly with air or steam.
The articles you linked show no reference to T/P relief valves failing to function when the tank is empty; actually, they point out that those accidents would have been prevented had a properly functioning T/P valve been installed. If you look at the design of one you will or at least should see that they will open whenever the pressure exceeds the preset value, whether the tank is full of water, partially full, or completely empty. Pressure is pressure regardless of the source.
In any case, my system is safe and now provides the added feature of preventing a major flood if something were to rupture while I'm away from home.
John
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(10-03-2017, 07:53 PM)blackhat Wrote: I got nothing wrong.
Saying you were not wrong is very different than not being wrong. The facts are what they are, and you entitled to your opinion and entitled to be wrong. Regardless, not worth arguing about it.
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(10-04-2017, 07:57 AM)jteneyck Wrote: Pressure is pressure regardless of the source.
In any case, my system is safe and now provides the added feature of preventing a major flood if something were to rupture while I'm away from home.
Pressure is NOT "pressure regardless of the source", a whole range of scientific laws prove that. Here is a link, if you want to learn more.
http://www.westfield.ma.edu/cmasi/gen_ch.../pvnrt.htm
You have the information now and can make an informed choice. If your system is safe to your level of comfort, it seems you have achieved your goal.
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(10-04-2017, 04:25 AM)jlanciani Wrote: Comparing the failure mode of a latex balloon to a steel tank is about the most rediculous thing I have read here in a long time.
Put a piece of duct tape on your balloons and repeat your test by poking the pin through the tape and let us know the results...
I'm guessing you are not an engineer or a technical person (or English, apparently - the red line under "rediculous" is warning you it is spelled incorrectly).
Your duct tape experiment is an interesting test, but does not demonstrate the different behavior of gases and liquids. That was the point of the balloon experiment, and why it is such a common and widely used demonstration.
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(10-04-2017, 12:46 PM)geek2me Wrote: I'm guessing you are not an engineer or a technical person (or English, apparently - the red line under "rediculous" is warning you it is spelled incorrectly).
Your duct tape experiment is an interesting test, but does not demonstrate the different behavior of gases and liquids. That was the point of the balloon experiment, and why it is such a common and widely used demonstration.
Yay, I misspelled a word and you caught it. I'm glad you have nothing better to do today but to be the spelling sheriff.
My point is that using a latex balloon as an analog to a steel tank is invalid and disingenuous. I fully understand the differences between compressed gasses and compressed liquids, I'm not so sure you understand the difference between a latex balloon and a water heater.
Oh and by the way, I am a fairly successful technical person, what exactly are your qualifications.
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(10-04-2017, 12:40 PM)geek2me Wrote: Pressure is NOT "pressure regardless of the source", a whole range of scientific laws prove that. Here is a link, if you want to learn more.
http://www.westfield.ma.edu/cmasi/gen_ch.../pvnrt.htm
You have the information now and can make an informed choice. If your system is safe to your level of comfort, it seems you have achieved your goal.
I'd be happy to discuss the universal gas laws, as much as you want. Which one or ones do you think prove that the pressure exerted by a gas is somehow different than an equal pressure exerted by a liquid?
John
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(10-04-2017, 01:08 PM)jteneyck Wrote: I'd be happy to discuss the universal gas laws, as much as you want. Which one or ones do you think prove that the pressure exerted by a gas is somehow different than an equal pressure exerted by a liquid?
Which one(s) do you think does not? If "pressure is pressure" the results of the balloon experiment would be the same.
Another difference - gas is compressible, water is essentially not compressible. As an example, water in the cylinder of an IC engine will usually destroy it, gas such as gasoline vapor does not.
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(10-04-2017, 12:58 PM)jlanciani Wrote: Yay, I misspelled a word and you caught it...
My point is that using a latex balloon as an analog to a steel tank is invalid and disingenuous.
The point is if the simple details like spelling are incorrect, the technical information is likely incorrect as well.
I understand that is your point, I'm just pointing out it is a baseless and invalid opinion - to which you are entitled.
Regardless, don't see much value in debating it futher.
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(10-04-2017, 03:50 PM)geek2me Wrote: The point is if the simple details like spelling are incorrect, the technical information is likely incorrect as well
You forgot to mention your qualifications but this statement tells me everything that I need to know about you.
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