If your water hammer arrestors are not doing the trick, I have to wonder if they are located and/or sized properly? Water hammer is not a "pressure" phenomenon - it's a "mass flow" phenomenon where the sudden stoppage of a rapidly flowing mass of water in the pipe causes the noise/motion (and a somewhat more legitimate "fear for the pipes.") Arrestors should be located at the ends of lines, especially those lines that serve items with rapidly closing valves (such as solenoid valves in washing machines and dishwashers - but modern 1-lever faucets can also be closed very quickly relative to old multiple-turn two-handle faucets.)

As is clear from the code languange (and also supported, IIRC by other questions about pressure that have passed through here) 80 PSI is a typical high limit on devices (especially toilet valves, IIRC) being happy. So 75-80 PSI should be perfectly acceptable if you like high pressure and have pressure higher than that.

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P2903.3.1 Maximum pressure. The static water pressure shall be not greater than 80 psi (551 kPa). When main pressure exceeds 80 psi (551 kPa), an approved pressure-reducing valve conforming to ASSE 1003 or CSA B356 shall be installed on the domestic water branch main or riser at the connection to the water-service pipe.

To make a long story short, I'm installing a pressure reducing valve (PRV). However, I'm not sure where I should set it. I've gotten used to the high pressure, and I'm afraid lowering it will be disappointing. At the same time, eliminating water hammer, and not worrying about damaging fixtures would be a good thing.

All residential water piping systems that I'm familiar with have considerably higher pressure ratings (160 @ 73F for much PEX tubing, for instance, dropping to 100 or so at 180F where your hot water lines should never be due to scald potential) - 400-800 PSI for 1/2 & 3/4 copper pipe (type M) so there really is no valid reason to "fear for the pipes" based on water pressure of 75-80 PSI.

A homeowner or plumber can accomplish this by consulting the pressure regulator manufacturer's instructions. The adjustment mechanism is usually a screw on top ...

Assuming metal pipe, I'd set it to about 60, because that's a good compromise between too-high pressure and disappointingly little pressure. That's what most well pumps I've seen are set for, and significantly less than most municipal water systems (I've seen one city water system that delivered 125psi to the house). Much lower than 60psi and you'll be frustrated by the slow flow.

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Since the time I moved into my house, I've had problems with water hammer. More recently, I've had some faucets start to leak. I also noticed that after showers/baths, the hot water would surge when the sink faucet was turned on.

I've searched the internet, and found recommendations anywhere from 40 to 80 psi. Family Handyman says that "... 45 to 55 psi is ideal.". I've also found that most PRVs come preset to 50-55 psi. Other sources say that anything over 60 psi, may cause damage to the plumbing system. IRC requires pressure to be above 40 psi, so I know I want to be above that.

These types of repair kits typically include parts like gaskets, washers, bolts and springs, though it depends on the type of valve each kit is intended for. If ...

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Hot Water Outlet Connection Size. 215, Individual point of use or groups of fixtures, 12 gpm (45 lpm), 1/2″ (15 mm). 320, Groups of fixtures, 24 gpm (91 lpm), 3 ...

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After installing water hammer arrestors, and securing all the plumbing. I have reduced, but not eliminated the hammer. As for the surging water after a large hot water demand. I recognized that, as a symptom of a failed expansion tank.

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604.8 Water pressure reducing valve or regulator. Where water pressure within a building exceeds 80 psi (552 kPa) static, an approved water-pressure reducing valve conforming to ASSE 1003 or CSA B356 with strainer shall be installed to reduce the pressure in the building water distribution piping to not greater than 80 psi (552 kPa) static.

With resilient (not PVC/CPVC) plastic pipe, I'd go a little lower than that because unlike metal pipe, which has very strong, secure connections, plastic pipe has only clamp-over-plastic-over-barb connections, which can fail more easily than metal pipe. With PVC/CPVC, I'd go even lower because it gets brittle with age.

This 2 1/2" lead free dielectric flange pipe fitting is designed for commercial and residential applications such as the connections of piping of dissimilar ...

P2903.3 Minimum pressure. The static water pressure (as determined by the local water authority) at the building entrance for either public or private water service shall be not less than 40 psi (276 kPa).

Every Double Check Valve assembly shall be the exceptionally low head loss type – model ED132 – as manufactured and distributed by Arrow Valves Ltd – Tel 01442 ...

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In the end, my wife decided she wanted the pressure higher. So I ended up setting the PRV wide open to 75 psi. It's a bit on the high side, but below the 85 psi I started with, and below the 80 psi limit in IRC.

A Bronze Marine or Navy Duplex Strainer, sometimes called a twin basket strainer, is a type of filter built into a fuel, oil, or water piping system and it is ...

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Pipeline fitting protection - Check valves are used to prevent damage to equipment such as flowmeters and control valves, all of which can be damaged by reverse ...

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Protect potable water systems with Apollo double check valves. Our valves offer robust construction and easy maintenance for reliable backflow prevention.

In the process of replacing the tank, I took a water pressure reading in order to charge the tank. When I got a reading of 85 psi, I was slightly concerned. Especially when the instructions for the expansion tank, said not to charge the tank over 80 psi. Of course I went directly to the code books, and discovered that codes call for a PRV for pressures over 80 psi.

This flow rate calculator, aka water velocity calculator, calculates the exact flow rate based on velocity and pipe diameter.