You should have a pressure reducer valve at the entrance of the water into the house. Never saw a house without one.

You remove this cheap piece of crap

https://www.askmehelpdesk.com/attach...alve-photo.jpg

and replace with what 99% of homes outside TV have.

http://cdn.networx.com/media/532x552...8a991fc5cd.jpg

I think PennBF received exactly the right answer about what happened. Without a check valve (one-way valve), the water pressure in the house "floats" with the supply pressure and gets no higher. With the check valve installed, and no expansion tank, the water in the water heater expands as it heats, can't back up into the supply line, and over pressurizes the plumbing in the house. Or trips the T & P valve on the heater.

When I go on vacation and shut the water supply valve, I set the water heater to "Pilot Light" setting and depressurize a hot water faucet. The water shutoff valve is acting just like a check valve when it's closed. Maybe now I'll install an expansion tank on my water heater. Thanks for the heads up.

Thanks
 

Bob47, thanks for your input and explanation. The plumbing co. tried to explain it to me but was not as clear as you have. Again, thanks.:eclipsee_gold_cup:

The only thing out side my CYV is water meter assembly and ball on/off valve after the meter, it then goes into the slab/walls. When was the one way valves required? Housing range from 60s to 2016 here? My water heater has expansion tank, I thought this was to ilimate the thumping sounds from the water heater. My meter was replaced last summer due to leak. How do I know if I have or need one way check valve?

Good Question
 

That is a good question. I see something on our water heater that looks like the expansion tank that everyone is talking about but the plumber I had said we should replace it since it is not the right expansion tank. I would not know the difference. Since your water meter has been replaced it may be prudent to have a plumber decide if it is OK with the new meter. Would add we have a very good and honest plumber so am convinced he is right.:bowdown:

I believe it's not a check valve but a backflow preventer. If the house pressure is greater than the street pressure it vents.The expansion tank is for expansion of water pressure when the water is heating so the backflow preventer won't vent. The reason for the backflow preventer is that if the water main breaks and loses pressure all the homes would drain into the main possibly contaminating the main and leaving homes with air in the plumbing.I like the supply valves I don't use them I just turn the main off when doing any plumbing repairs.

follow up
 

Checked with Water Dept and they recommended having our plumber also check the PRV valve on the Water Heater. They had not heard of the problem before. Did say the home owners should have been advised of any meter replacements and added check valve. :bowdown:

Now I am confused because the plumber was called to replace a water heater and then to change out the water valves shut offs throughout the house and replace with upgraded. he told me to save my money and swore that these valves were sound? He would ave to replace 15 valves in my home I do know that if the expansion tank goes chance are one perhaps more of these valves will pop and shut off the water supply. Hmmm have to give more thought to this issue

The new meter has nothing to do with the expansion tank on your water heater. If there is a back flow preventer/check valve after the meter, you basically have a closed system, hence the reason for the expansion tank on the heater. As far as the push pull valve is concerned, I'm not aware of any major problem with these devices. I'd be more concerned about a blow out on the water supply lines on your washer and dryer, unless they are the stainless steel braided lines.

The OP may have an expansion tank that's shot. Rap it with the blunt end of a butter knife. If it doesn't sound hollow it's shot.

It's supposed to have water in it, how can it sound hollow?


Expansion tank - Wikipedia, the free encyclopedia

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If the diaphram is intact half the tank will contain air. A broken diaphram will produce a dull thud sound.

Not Expert
 

Heck, I am not an expert on water systems so can add little to the problem other than what I have been told. In the course of the discussions it was mentioned that when the water meter was replaced something was also done with the "Check Valve" and the home owner was to be told of the meter change/check valve adjustment or something to that effect. We were not told. I was also told the "push pull" valves are the cheapest and should be replaced when appropriate. We have a plumber coming this morning who is going to replace the bathroom push pull valves and also look at the extension to see if it is OK or replace it? The PSI for our area was checked and it is at 58psi and I understand it should be between 50 and 60 so it is fine. No one can tell us with any absolute definition why ours blew out and with the force it used. :bowdown:

End of Question
 

Hopefully this will be the end of the discussion since I have had a plumber look and fix it. It appears the "expansion" unit was the problem. When he removed it it was very heavy and filled with water. When I held the new one is was relatively light when compared to the old one. That was because it was half air and half water which is right.
As he explained it the cause of the pipe that was broken was because of the "shock" to the pipe because the expansion was bad. He said it would be good for anyone who believed their expansion was faulty to have it checked. He is an excellent plumber and is very fair in his charges. His company is "Holmes Plumbing" and his name is Charlie and his number is 352-787-9554. He is the same person who was at our home within minutes when we called with the broken pipe. :eclipsee_gold_cup: