Increased water pressure after changing water supply lines?

[JaCkaL829]

Hello,

As my title says, I'm experiencing higher water pressure in my house after I replaced some water supply lines. I cut out a section of 25-30 feet of older supply lines in my basement that was sheetrocked over. Every other supply line is 1/2" copper (some M some L) that feed my kitchen, bathrooms, etc. I removed the old supply lines since I though it was galvanized steel, but it turns out most of it was older brass supply lines. Anyway, now that I put in copper type m, I've been experiencing an increase in water pressure. I also notice now when my toliet stops running, or a faucet is shut off quick I'm getting water hammer. I believe some of that can be reduce by finishing up my job with adding straps for the longest run (20 feet), but I'm wondering if I should be concerned with the increase pressure? I've never had this problem, and I don't have a pressure reducing valve or anything like that on my house line.

Any information would be greatly appreciated, I feel like I've experienced water hammer before, but I've moved and replaced lots of water lines, that it's hard to keep track. I've never used those water chamber arrestors that go on the washing machine.

 

[Reach4]

1. Measure your water pressure. Pressure gauges that will go onto a garden hose thread are inexpensive and are readily available.

2. Put a water hammer arrestor at each valve that makes a bang when it shuts off.

 

[Sponsor]

 

[JaCkaL829]

1. Measure your water pressure. Pressure gauges that will go onto a garden hose thread are inexpensive and are readily available.

2. Put a water hammer arrestor at each valve that makes a bang when it shuts off.

I will get the water pressure gauge at home depot tomorrow.

As for the water hammer, I'm seeking the supply lines by the hot water heater shaking. Not sure if it's just because I need more straps on the lines, but there is no valve near there.

 

[Reach4]

As for the water hammer, I'm seeking the supply lines by the hot water heater shaking. Not sure if it's just because I need more straps on the lines, but there is no valve near there.

I am not sure what you are saying.

Usually you detect water hammer with your ears. Do you get a bang, or not?

Water hammer is caused by the moving water having momentum, but getting blocked suddenly. Bang. The water hammer arrestor will give the moving water a place to go during the slow-down.

 

[hj]

Changing the water lines would NOT increase your static pressure, but COULD increase the dynamic pressure and volume when you have a faucet turned on.

 

[Jadnashua]

Pressure is the same in the system whether through a soda straw sized pipe or a fire hose...but, as said, when you then ask it to flow a large volume, the dynamic pressure will drop much more on a small pipe because of the friction.

 

[JaCkaL829]

I purchased the water pressure gauge that attaches to my outside hose bib and got a reading of 90 psi. I believe that is too high. As for the hammering I secured my long runs with those ribbed clamps and created cross braces which has basically eliminated all of the hammering.

I would like to call my local town regarding the water pressure being so high. My wife who works in the same town, had an issue at her office when a pipe broke and flooded their basement. When the plumber fixed it, he said it will happen it again and it's because the pressure is so too high. That's what I'm looking to avoid. One more side note to add that I didn't put in my original post. This past Spring my water main on/off valve was dripping a little. It was an older globe valve, and even though I had tighten it a few times in the past, I decided to replace it with a 1/4 turn ball valve. My friend helped me replaced it, and he turned the water off at the curb using a curb key. I'm now wondering if he opened it up too much creating the higher pressure? When I spoke to my plumber last night regarding the issue he said the older pipe may have restricted the water flow at the joints, but I never mentioned the curb key. I'm wondering if lowering my pressure could be as simple as slightly closing the valve at the curb? If I didn't have a wedding to go today, I'd ask my neighbors to test their pressure just to see what they're measuring at.

I've read about the pressure reducing valves, but I don't like the idea that a high pressure comes into my house, than I reduce it, seems like the reduction would be prone to more problems. I have no experience or background on this, I'm just thinking that pressure getting bottlenecked in my basement wouldn't be ideal.

 

[Reach4]

I'm now wondering if he opened it up too much creating the higher pressure?

That cannot happen.

 

[hj]

The city supplies the "high" pressure in order to service the ENTIRE town, not just your house. If you do not like the pressure it is YOUR responsibility to install the pressure reducing valve. You do NOT increase, or decrease, pressure by opening or closing valves, that only changes the volume.

 

[JaCkaL829]

Thank you both for the responses. If the pressure incoming from the main is standard, would you recommend putting on a pressure reducing valve with the readings I got? It seems pretty basic, just cutting into the main and putting it on. I don't mind periodically checking it and making adjustments.

 

[Reach4]

Thank you both for the responses. If the pressure incoming from the main is standard, would you recommend putting on a pressure reducing valve with the readings I got?

I would not do it with 90 PSI coming in, but many others would. If you put a PRV in, you will need to have a bypass PRV, or you need a thermal expansion tank. PRVs are not as trouble-free as you would hope. Keep monitoring. The water pressure might be higher at times. You can put your pressure gauge inside so that you don't have to go outside in the middle of the night to check the pressure. You can attach the gauge to the water heater drain.

I would put in water hammer arrestors for quick-closing valves. I would close the tub faucet slower. Even with a PRV, you should probably have arrestors on quick-closing automatic valves such as for the washing machine.

I am not a pro.

 

[Jadnashua]

Plumbing code calls for residential applications to not exceed 80psi...so, at 90psi, technically, you should have a prv. Note that at night, your supply pressure could easily be higher as the town refills the water towers, and few people are using water. The goal of a prv is to keep the pressure at a constant, safe pressure. If you opt for a bypass version of a PRV, your pressure WILL periodically rise to slightly above the street pressure before it can open the bypass and return back to the street...IOW, it cannot fully regulate the pressure. The reason for this is that a PRV creates a closed supply system. When your water heater runs, the act of heating the water causes it to expand. For practical purposes, your plumbing system is not flexible...it does not expand to compensate for the increased water, so the pressure spikes. It can easily get high enough to open up the safety T&P valve on your water heater (150psi), but if you have a by-pass PRV, and your supply pressure is 90psi, that would open before the WH's T&P valve would be opened. All of that flexing from the pressure rising and falling is stressful on the seals and hoses (faucet, toilet, washing machine, etc.) in the house. They much prefer a constant pressure. To eliminate that variation, an expansion tank is required to provide a place for that expanding water to go until you open up a faucet again. When sized and installed properly, there's an almost immeasurable variation in pressure when the WH runs after hot water usage.

Also note, that as maintenance is done on most water supply systems, they are installing check valves to the house. This also creates a closed system, and a bypass on a PRV would then become useless. The only solution then that is practical is to have a working expansion tank. A pressure relief valve could work, but it would then be dumping water each time the WH ran...IMHO, a lousy solution.

 

[JaCkaL829]

This morning the water dept called me back, and basically said the same as you guys. Pressure can't be altered, only by the homeowner in their home after the meter.

I did measure my neighbor's pressure this afternoon, 4 houses (2 to the right, 2 to the left) all measured 100 psi, including my home.

I've read the posts multiple times now, it seems like a prv also requires an expansion tank because my system will become closed.

I appreciate all the replies. At this time I would like to investigate the prvs and expansion tanks more.

I would also like to call and speak to a few local plumbers to get their opinion on the issue. I already have a feeling I should make the improvements, especially considering I replaced all my old brass pipes for fear of one breaking and flooding my basement. This high pressure is a concern of mine, and I believe my neighbors just aren't aware of the issue.

 

[Jadnashua]

100psi is 25% higher than the regs allow inside the home. Yes, you could live with it (your showers will be more invigorating if you like that sort of thing), but it does wear things out and risks a catastrophic failure. Most people live just fine with lots lower pressure.

 

[JaCkaL829]

100psi is 25% higher than the regs allow inside the home. Yes, you could live with it (your showers will be more invigorating if you like that sort of thing), but it does wear things out and risks a catastrophic failure. Most people live just fine with lots lower pressure.

Thank you for the help, and information. I'm close to buying the pressure reducer valve, along with the expansion tank. My plumber didn't think the tank was needed with a prv since the prv has a bypass. But reading the watts paperwork, it seems they recommend it. Everything I read online says it doesn't push water back to the main till 150 psi which would make the pressure all out of whack. The guy at the plumbing store said I should do both, and that's what I'm leaning towards now.

 

[Jadnashua]

If the pressure rises to 150psi, the T&P valve on the WH will (or should!) open unless something begins leaking beforehand. A bypass on a PRV can't open until the outlet pressure exceeds the inlet pressure (it must have more to push the valve open against the incoming pressure). I'd be surprised if it was much more than the inlet pressure, though...150psi would be a bad design choice, and even then, if your incoming water pressure exceeded that, it couldn't push back at all! IMHO, the bypass is not worth much and might mask the problem of the ET failing. It's just one more thing that can fail. Simpler is better.

Keep in mind that many water supply systems are now installing or have already installed check valves, so a bypass would do nothing. They are doing this to help prevent pollution from potentially being pushed back into their system, protecting the rest of their customers. This is one reason why many places are requiring the installation of an ET...they either have, or intend to make all of their customers into closed systems.