high water pressure

I recently put a pressure gauge on my water heater drain faucet, I got 140. That is the reason the TPR valve is dripping.
At first, I thought it was due to thermal expansion from the water heater.
The pressure would go down to 40 as soon as I turn on the cold water faucet. The pressure would creep up after I turn off cold water. Note, the water heater wasn’t heating because I only turned on/off the cold water.
That means the pressure isn’t from thermal expansion, right?
Does that mean my street water pressure is too high?
I have pressure regulator in my house. It reads 25-75.
So what is the problem???

Sounds like you need a new Pressure Reducing Valve…but I am not a plumber, which is who I would recommend looking at the issue, and repair as needed.

Regulator isn’t regulating… The water to the water heater. Spring type regulators sometimes get stuck. Take your guage and put it on a sillcock to test house pressure. If it is high also then have service on regulator or replace.

Thanks for your suggestion. I will try it on sillcock tomorrow.
But I thought it should be the same as they are all connected together.

Without knowing what the system looks like there is no way for me to say that all water is reduced. Since when you turn on the cold the press. drops the entire water system is probably connected to one faulty press. regulator.

Hard to believe there is 140 lbs. at the street, now that is really off base.

Lynn, are you sure the pressure gauge your using is reading correctly?..I think I would try a couple different pressure gauges…that is really odd.

Dale I’ve seen it about that high south and east of Dayton, so I guess I just took it for granted.

My street pressure is 160 psi.

Your regulator is bad, plain and simple. The label that reading of “25 - 75” is just the range of the regulator - when it’s functioning properly.

160 lbs unreal…:shock:

Getting any Fire or Smoke up you’re way Jeff?----:shock:

When I was in the Underground Pipe Business, water, sewer, storm, large diameter pipe, 4 in. to 60 in…I only tested PVC or Transite at 190 lbs, and if there was a pocket of air in a pipe, I have seen the pipes come right out of the ground and tip a car on its side (after the pipe failed) when I was testing the pipe for the City inspector…!!!

Wow, that’s amazing Dale. Good thing it was the car and not you. :shock:

No smoke here. We’re about 15 miles north/west of this one. Freeways are sure tied up though.

The pressure gauge still reads more than 145 on the outdoor sillcock. So the problem IS water pressure from street is TOO high.
Is the water company’s responsibility to set the proper pressure when connect to my home?
The pressure regulator (the failed one) is connected before water meter. Does this belong to water company or mine? I called my water company, but I don’t know when will they show up.
Any estimate to replace the regulator if I call plumber from yellow page?

The regulator is your responsibility.

Thanks Jeff. Do you mean it’s mine even if it’s before the water meter?
So the water company is not responsible for regulate the pressure? No wonder they still have shown up yet.

Be sure that you are not confusing a backflow preventer with a pressure regulator.

Generally, anything before the meter is their property, however, they are not required to reduce or regulate your supply pressure. If there is a regulator before the meter, they can remove it completely if they desire. . .

In the Porter Ranch section of Northridge, CA, the street pressure is 200 psi plus. I don’t remember how high exactly, but maybe even as high as 275 psi. Even my sprinklers need to be regulated, and I replace regulators about every two years. In fact ,last week, my automatic sprinklers stopped working, and after trouble shooting for about an hour and re-reading the manual one diagnosis suggested that the pressure was excessive. Sure enough that was the problem, and after replacing the regulator the sprinklers starting working again. Nothing is as it seems here in La-la-land.

Hell you need very high water pressure out there just to put out all the damned fires :frowning:



Call it urban sprawl. Here in KC, so many new homes, and no money spent to put in new pumps. So, cities just turn up the pressure on the old pumps to be able to supply the new homes. Had a 160# reading just this week. Home was only 4 years old. No regulator. Every faucet was dripping, and had corrosion around all of the cut-offs. Duh.