New home - 85 psi water pressure

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Davej

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I am a new homeowner, and I thought my water pressure was too strong because water was going everywhere when I turned on the faucets. I asked a plumber to come over, he put a gauge on the valve going to my washing machine in the basement, and it read 85 psi. He said he likes to see 60-85 psi so I was fine. As for the water going everywhere, he cleaned a couple aerators, replaced others - everything is fine now and he didn't even charge me!

I called our city building inspection department after the plumber left, and they said 85 would be one of the highest they have seen, but that under 90 psi is fine.

Should I be concerned at all? 85 psi seems borderline high from what I've read on this forum and others. But I have two people telling me its no big deal.

My meter is inside in the basement, if I had a pressure regulator it would be there correct?
 

Gary Swart

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I think there are different opinions on how high is too high, but in my opinion 85 is too high. I have mine set at 50 and feel very comfortable with that. A bit higher would be OK. If this was my house, I'd install a pressure regulator valve on the incoming supply line and follow that with a thermal expansion tank. The PRV will create a closed system. When water is heated, it expands. In an open system, this expansion is absorbed by the city water main with no problem. However, the check valve in the PRV prevents this. The result is the T/P valve on the water heater will release the excess water and that usually causes a minor flood. If the T/P doesn't open, then the excess is released through a leaky toilet valve. No mess, but not a good situation either. No big deal? Maybe not, but maybe so. Too much pressure causes stress on toilets, and washing machines. You just don't need that much pressure in your home.
 

Sluggo

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davej-
Given your setup, it is likely that -- if there is a pressure regulator -- it is near the meter, but it could be anywhere after that and before any lines branch out. Do you know what a pressure regulator looks like?
 

Themp

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For 30 years I have kept my pressure reducing valve at 45 psi. A little low but my shower is fine and faucets we are used to. I do have a branch before the pressure reducing valve for two outside bibs and they are at 90psi, city water pressure. Love these for washing the car and such. My son in the same city likes 60 psi for his house.

I did have to replace my water line to the house and the inspector made me remove the branch before the pressure reducing valve as he said it was not code. The plumber was nice and put it back after the inspector left. I know this is bad, but heck the pressure reducing valve of a few of my neighbors are bad and they love the 90 psi and have decided to not fix it.
 

Davej

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OK, thanks for the input.

I will probably have a PRV / thermal expansion tank installed. The possibility of water where it shouldn't be seems pretty destructive, so I don't want any problems!

I do wonder what my plumber will think - asking him to perform work he doesn't recommend, and getting a permit for something the city says I don't need :-/
 

hj

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Our city does NOT care if there are hose bibb, or irrigation systems, ahead of the PRV, and I like to set them at 75-85 psi, so you are fine. If you want something done, even if I tell you it was not necessary, then I will do it. BUT, why would he get a permit, which just adds to the cost including labor charges?
 
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WorthFlorida

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... In an open system, this expansion is absorbed by the city water main with no problem. However, the check valve in the PRV prevents this.

I believe all water meters have a built in check valve to prevent possible contaminated water from backing up to the water main such as when the water expands as it is heated in the water heater.
 

Jadnashua

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I believe all water meters have a built in check valve to prevent possible contaminated water from backing up to the water main such as when the water expands as it is heated in the water heater.

Most (all?) newer construction uses a check valve, but there are probably millions of water meters out there that do not have one.

Depending on the code that your locale has adopted, water pressure above 80psi should be reduced to 80 or below. Keep in mind, a pressure reading in the middle of the day may not be the same as at night when nobody is using any water, and they may be trying to refill their water towers or reservoirs. The only way to tell the peak pressures is to use a gauge and leave it on there for at least 24-hours and have a peak reading indicator (tattle tale) hand on it. You might find that the overnight pressure gets LOTS higher. Supply hoses to things like your washing machine, ice maker, faucets, toilets, may be tested to higher pressures, but are designed around a nominal 80psi max pressure.
 

hj

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quote; I believe all water meters have a built in check valve to prevent possible contaminated water from backing up to the water main

You believe wrong.
 

WorthFlorida

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Thank you for your correction HJ. I checked water meters on line and non of them mention backflow prevention. I checked with my local water department, Palm Beach County Water Utilities Dept (FL). Below is from the Uniform Policies and Procedures. At the meter on the customer side there is a backflow prevention assembly. I was under the impression that it was part of the meter.

7.3.2 LOCATION AND ACCESS REQUIREMENTS
Backflow prevention assemblies shall be located on the Customer’s side of the point of service, and
installed in accordance with the Department’s Minimum Design and Construction Standards, Palm
Beach County Plumbing Code, and manufacturer specifications. Additionally, the Customer shall
maintain access to the assembly for the purpose of testing and maintenance.

At this link, click on Polices and Procedures (left column) and it will open a PDF document. See chapter 7
http://www.pbcgov.com/waterutilities/inthenews/
 

Jadnashua

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Since they mandate a check valve, you should have an expansion tank installed in your water system. Depending on what your water heater was doing at the time the plumber checked the pressure, it could easily have been from the WH running. With a closed system, and no expansion tank installed, the water pressure can easily rise to the point where the T&P safety valve on the WH opens to relieve it (typically, 150psi). The only reason it may not get that high is if the check valve is not working properly, or there's a leak somewhere in the house to relieve that pressure.
 

Gary Swart

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I have heard that at least some new water meters do that the check valve, but certainly not all meters are so equipped. I would encourage you to spend $15 or so and get yourself a pressure gauge. Any hardware store should stock them. Connect it to a hot water faucet then drain some hot water out of the tank so that it will begin to heat. Watch the gauge. You will be amazed at how fast the pressure rises and how high it will go. Again, 85 psi is not dangerously high, but it is still higher than necessary and I would recommend a PRV and expansion tank.
 

WorthFlorida

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I looked up the installation & operation manual instructions on the Rheem site and they recommend an expansion tank for a closed system. I then found the plumbing code for the State of Florida. http://ecodes.cyberregs.com/cgi-exe.../indx/ST/fl/st/b900v10/st_fl_st_b900v10_6.htm

607.3 Thermal expansion control.

A means of controlling increased pressure caused by thermal expansion shall be provided where required in accordance with Sections 607.3.1 and 607.3.2.

607.3.1 Pressure-reducing valve.

For water service system sizes up to and including 2 inches (51 mm), a device for controlling pressure shall be installed where, because of thermal expansion, the pressure on the downstream side of a pressure-reducing valve exceeds the pressure-reducing valve setting.

607.3.2 Backflow prevention device or check valve.

Where a backflow prevention device, check valve or other device is installed on a water supply system utilizing storage water heating equipment such that thermal expansion causes an increase in pressure, a device for controlling pressure shall be installed.
 
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Jadnashua

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There are a couple of ways to limit the excess pressure, and personally, I think the second one is kind of silly except in very specific circumstances and they are: an expansion tank, or a pressure-relief valve. Both are mechanical, both wear out, but with a pressure-relief valve (not the same as a pressure reduction valve, watch the acronyms!), whenever the pressure rises, it dumps water...kind of wasteful IMHO. They work better as an emergency safety valve (like the T&P valve on your WH).
 

Davej

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So I did get a pressure gauge, read it a couple times and it typically read 85-95 psi and once 100 psi. I had a different plumber over for a broken pop-up drain assembly, asked him to hookup his gauge and it also measured 95 psi.

So he came back and installed a Zurn Wilkins model 600XL pressure reducing valve and a Watts PLT-12 4.5 gal thermal expansion tank above my power vent 50 gal hot water tank. He set it at 75psi - does that sound reasonable?

I did try and get a permit for the work, and the city said they don't issue one for this kind of job. I just like wanted a set of eyes to know if the work was done well or not. This is my first home and I've been disappointed with other people I've had work on the house, which made me think I should start pulling permits all the time.

That said, I did call the inspector with a question about offset toilet flanges and he didn't know what that was :( I was kind of disappointed by that, made me think having the city's stamp of approval wouldn't be an indication of quality workmanship anyways - which is what I wanted it for.
 
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Terry

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75 PSI sound nice. I prefer that over the factory set 50.

Not all inspectors have worked in the field. Some have, and are very good. It sure varies by locality.
When I was doing a lot of commerical work, I always called and met with the local inspector "before" doing the work to get his/her take on what the pet peeves were. I was plumbing in meat markets for a chain of grocery stores, and basicly the same plan was done nine different ways. Every inspector had something different that they wanted done. I was banging them out quickly, and the only problem I had was with a Tacoma inspector that showed up that was not the original one I had talked to. His beef was that I was "working in the wrong county"
It wasn't the work.

I don't really like offset flanges. They cause a restriction in the flow of the drain. Why do you need an offset?
 

hj

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quote; I did call the inspector with a question about offset toilet flanges and he didn't know what that was

That is strange, because even if he used to work at Home Depot, he should have known about them.
 

Terry

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quote; I did call the inspector with a question about offset toilet flanges and he didn't know what that was

That is strange, because even if he used to work at Home Depot, he should have known about them.


Oh no. He may not even have Home Depot experience? :(
 
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