Hi all,
Our water bill has been a bit high, so I'm trying to understand the cause of it. This led me to testing our water pressure. I went out and bought a water pressure gauge, to test with. Here's where I'm thoroughly confused...

I hooked up the gauge on a hose bib, next to the water pressure regulator. My static water pressure is 110psi. When I turn a sink faucet on in the house, my water pressure is at 55psi. I believe this is my dynamic water pressure (? ).

I've been told that my water pressure should be between 40-80psi. So, here's my question:

Is that 40-80psi the STATIC or DYNAMIC water pressure reading? I tried adjusting the pressure regulator when no water was turned on (static), but my reading never dropped below 110psi. Could this mean my pressure regulator is bad?

Thanks in advance,
Gary

Static pressure should be 50-60 range.

Thank you very much for the quick reply! I called the water dept, and they said my static pressure at the street is 130psi. My gauge is reading the static pressure at 110psi on all of my hose bibs. So, my pressure is obviously way too high.

I tried adjusting the pressure valve (turned the screw counter-clockwise), but it never drops below 110psi. Could my pressure valve be bad? If so, is it difficult to replace... or would I need to contact a plumber? It looks like it's just held on with a nut on both sides. I'm not sure if I could simply turn off the main water, unbolt the old pressure valve, and replace it with a new. Wishful thinking, I'm sure... but thought I'd ask.

Thanks again,
Gary

After making adjustments open a faucet to release pressure, then take another static reading. Yes, the last one I replace was just as easy a you describe. Available at Home Depot and the cheap ones are in the $30 range. A couple of pipe wrenches and some pipe thread sealer.

Many hose bibs are connected BEFORE the pressure regulator so static pressure there may not be too high with 130# at the street. With no water turned on, you won't see any change in the static pressure. Adjust pressure with water running, or adjust PR and flow the water to see if it changed. 110 is static, 55 is dynamic. 55 # drop off seems a bit high with only 1 faucet flowing. You cannot relate static pressure and dynamic pressure without knowing pipe size. For example, you could have a load of pressure on a very small pipe and get hardly any flow because the pipe becomes a critical orifice.

Thanks again for the replies. I tested the static pressure from within the house (at the washer line). The static pressure (with all the water off) is 110psi at the washer inside my house. Once I turned on the sink faucet, it dropped to 55psi.

I'm not sure which pipe size you're talking about. I have a shutoff valve connected to the pipe coming into the house. Shortly after that, is the pressure valve. Shortly after the pressure valve, I have a hose bib. The piping there appears to be about 3/4", but I could be wrong.

I also tried adjusting the valve with the water running, but it didn't help any. I'm still at 110psi when I turn off my faucet.

Sounds like I may need a new pressure valve? My PRV says it's a Watts STD 50, range 25-75.

Thoughts? Time to replace it possibly?

Thanks!
Gary

Pressure regulators cannot reduce a pressure downward UNLESS there is flow.

Backflow preventers (check valves) do not work with pressure regulators without an expansion tank.

It does SEEM that your PRV is faulty.

Thanks KISS. I'm going to run down to Ace, Home Depot or Lowe's and see if I can find the same size PRV.

Gary

Sorry guys... one more question.

My static reading (from every hose bib, and from within the house) is showing 110psi.

When I turn on the water, it dropped to 55psi. I turned the valve counter-clockwise while the water was on and I can see the pressure drop. I went down to 10-20psi, and water was slowly flowing from the faucet. The second I turn the water off, the gauge jumps back to 110psi.

There obviously should be close to 100psi discrepancy between my static and dynamic numbers. Would a faulty PRV do this? I thought it may be faulty, but I'm definitely able to slow down the flow while the water is running.

Any ideas?

Thanks,
Gary


Oops, meant to say:

"There obviously should NOT be a 100psi discrepancy between my static and dynamic numbers".

Pressure should not change much.

So what would cause it to change this much? The PRV?

Thanks

A very small water line would have a large pressure drop which I doubt you have or the PRV.

Awesome - thanks for your input. I'll move forward replacing the PRV.

How old is your house? What kind of pipes? Copper. Plastic or galvanized? The pressure loss, after you open up faucets,
May be a volume problem because of mineral buildup in your pipes. 110 PSI is too high. It puts a strain on joints and valves. The average house pressure is 45 PSI, ( that's why water towers are 100 feet high).
Before you replace the PRV try this;
1. Close the gate valves before and after the PRV. Open
The bypass valve slowly in the bypass line and blow
The system down. Care should be taken not to open
The bypass completely to prevent the safety relief
Valve (if installed) from popping off. After blowing down
The system, close the bypass valve.
2. Loosen the lock nut on the adjusting screw to allow
Adjustment. Relieve the adjusting spring. See Figure
2-1.
3. Slowly open the inlet side gate valve to the fully open
Position, and partially open the outlet valve so only a
Small amount of fluid can pass.
This bulletin should be used by experienced personnel as a guide to the installation of the Model GD-24 Pressure
Reducing Valve. Selection or installation of equipment should always be accompanied by competent technical
Assistance. You are encouraged to contact Armstrong International, Inc. or its local sales representative for additional
Information.
1. An Armstrong ìYî strainer (20 ñ 100 mesh, depending
On liquid quality) should be installed before the PRV
To reduce the chance of dirt fouling.
2. Pressure gauges should be installed before and after
The PRV.
3. Piping a bypass line with a globe valve around the
PRV will allow system operation while the PRV is
Being serviced. Install only if fluid cannot be shut-off
To service PRV.
4. Do not install quick opening or closing valves
Downstream of PRV.
5. Install the PRV with the flow in the direction of the
Arrow on the body.
Improper adjustment of the pressure reducing valve may cause hunting, improper control, and possible damage to the
Valve itself. Adjust the valve as follows:
4. Slowly turn the adjusting screw clockwise until the
Desired pressure is obtained on the downstream
Pressure gauge.
5. Slowly open the outlet valve to the fully open position.
6. Adjust pressure again after system stabilizes.
Turning the adjusting screw; Clockwise increases
Pressure and Counterclockwise decreases pressure.
7. Tighten the adjusting screw lock nut after adjustme
Good luck, Tom

Tom,
Great information - thanks! My home is 5yrs old and has copper pipes. I'll give this a try, before I go through replacing the PRV.

Thanks,
Gary

I believe you need a PRV. Look to see how it is connected, some are pipe thread, some are sweat-Hope for pipe thread.

Status update, and another question :)

I'm pretty confident that my PRV is in fact faulty. I ran to home depot, and picked up a 1" PRV. Unfortunately, the one I bought has larger gaskets... so the nut will not thread onto the PRV. So, I'm just going to purchase the same one I currently have.

Here's where I need your help. There are about 10 different connection options to choose from. I want to make 100% sure I get the right one.

This is EXACTLY what my existing PRV looks like:
http://www.westsidewholesale.com/media/catalog/product/cache/2/image/262x/9df78eab33525d08d6e5fb8d27136e95/5/7/575017-1.jpg

When I go to Watt's website, here are the available connections:
Threaded, solder, PEX, quick-connect and CPVC with both union and double union connections.

So, which one do I need? Mine has threads on the OUTSIDE, so I know they're not female threads. I also know they're not solder connections. Would mine be considered union connections?

Thanks in advance,
Gary


So, it looks like I need an NPT threaded double union. Does this sound correct?

Thanks!

Show us a picture of your existing PRV

Thank you very much Harold! It looks like I need a double union connection, since the nut will thread onto these exterior threads.

Thanks again,
Gary

Repeat, one end should screw on to a threaded male adapter, the other end would be a union connection.

Thanks Harold. The piping has a nut, with a lip/flare on the end of the pipe (so the nut won't slip off). These nuts screw onto the exterior threads of the PRV. I won't be using the interior threads of the PRV, only the exterior threads.

I'm just overly confused with the terminology. What is a union connection? Is that the existing nut that is on the pipe?

I just know that I need EXTERIOR threads on the PRV. I'm just not sure which Watts model I need (N45B Water Pressure Reducing Valves , Water Pressure Reducing Valves - Standard Capacity, Water Safety & Flow Control - Watts (http://www.watts.com/pages/_products_details.asp?pid=3429)).

Thanks,
Gary

Show me a picture of your valve. All you need is a valve to fit the size pipe you have.

Unfortunately, I reinstalled the PRV after the Home Depot one was a tad too long. So, I only have a picture of it installed. The PRV is 1".

MobileMe Gallery (http://gallery.me.com/shacall#100022/N45b%20PRV%201%22&bgcolor=black)

Does this help? You'll see the union connectors (?? ) on both sides of the PRV. I simply loosened those, and the PRV popped right out.

Thanks!

File appear to be password protected. To post pictures, convert to JPEG, click on "Go Advance" button below "Answer this Question" block, browse to find picture, click open, click upload.

How long is a tad to long?

Sorry about that. Hopefully this will show up:

Thanks!
Gary

Show me a pic of the pipe to the left.

Unions vs. Couplings

Couplings: Require space to connect pieces of pipe/tube together.

Repair Couplings - They are missing the stop in the middle of the fitting, but it still requires that the fitting be able to move out of the way.

Unions - Generally used as a point of disconnect for appliances. They require no additional space to remove. They are also used when items need to be replaced periodically like water meters and PRV's. Usually two wrenches is all that's required to be able to remove them.

Get a 1" Sharkbite coupling from Home Depot. Cut house side pipe (left side) at a convenient place. Install new PRV to street side pipe, install cut off piece of pipe to PRV. Slip Sharkbite coupling onto house side pipe. Measure the amount of piping that has to be removed from the cut off piece of pipe to fit in Sharkbite. Remove cut off piece of pipe from PRV, cut off the excess pipe, insert in Sharkbite then reconnect to PRV.

Just wanted to thank everyone for your help and fast replies. It really is appreciated. Unfortunately, I'm leaving out of town and won't be able to get back to this until Tuesday. I'm going to try and run down to Ace Hardware and Lowe's, to see if any of their PRVs will work. If not, I'll get one ordered.

Thanks again - I'll check back on Tuesday.

Shacall:
I have same problem at home which is about 50 m below the city average. At nigh when no body consumes water I have all the water coulmn for myself and pressure is very high.

I was looking for static pressure regulator but my cdriteria tells me that I wount be able to find it, because it is not possible to do it.

You will always have the whole system at 110 psi while no water is being consumed. Your regulator has nothing wrong and will only work for water running though the tubing.

Whatever you do, as soon as you close the faucets or any leak, pressure will rise up to 110psi.

The only way is to have an elevated tank, fill it and consume from the tank. The money you need might be quite high but there is no other way. You may use an underground tank and a pump also.

Sorry for my english

Fer, I think you are wrong on that idea. A person could simply obstruct the line coming in to the house to lower pressure when water is being used. My understanding is that the PRV regulates pressure on the house side of the valve and will not allow it to get any higher than the pressure it is set for.

pressure will rise up to 110psi

I also disagree. A PRV wouldn't be much good if the above statement were true.

P.S.
This is a two year old post.

Friends,
I am an electronic engineer and could not argue very much on this subject. However some criteria on fluid mechanics tell me that any regulator will actually regulate fluid pressure on the consumer side while water is flowing.

I am in trouble here at home because water pressure increases very much in the evening. I realized only after two severe leaks appeared. Fortunately both were in the garden and for the time being, I am closing the main valve at night because I am afraid of having some leaks in the interior of my house

If you know of any device that regulates pressure at the consumer side and it remains on that value some time after we close all consumer points, please let me know so I can buy it.
Regards

Fersolavi

As everyone here has been stating a PRV (pressure regulating valve) keeps water pressure from exceeding a set pressure in your home.

Here, if you set the PRV at say 65 P.S.I. then water pressure coming into your home will not exceed that pressure.

To test this and to confirm/set the pressure at the PRV you would use a hose bib pressure gauge at an outside faucet.

Any questions just let us know, OK?

Mark

Ferslovi, no problem with your English, having read all these posts, you had a very logical answer. Regulators will not control the pressure in a system unless there is flow, no exceptions. Regulators help minimize damage to quick shutting valves like dishwashers and washing machines. They also reduce the velocity of water flow which maximizes pipe life Most systems will have high static pressure which is always present whenever water is not flowing.

I understand fluid mechanics as well as the next guy, but you guys couldn't be out in the field working with these PRVs very much! Here, no matter what you guys say, if I run water from a high pressure system, say 110 P.S.I. as Ferslovi presented, and I have the PRV set (and confirmed) not to exceed 65 P.S.I. then the system, whether open and flowing (dynamic) or in the closed/non-flowing position (static) will NOT exceed 65 P.S.I. (plus or minus a couple P.S.I.) unless the PRV is defective.

How do I know this with certainty? I know this as I set every PRV using a hose bib pressure gauge on every job I install a PRV on as I presented in my last post above. If I set the PRV at 65 P.S.I and the street pressure is 110 P.S.I, the hose bib pressure gauge doesn't exceed 65 P.S.I. whether I run the water or leave the water standing (all valves closed).

Argue if you want, but your argument has "leaks in it", I assure you!

Mark

Mark,
What happens if the incoming pressure spikes to 140 then returns to 110?

You know, Harold, I've simply never seen a situation like that...

In my experience, if I set a PRV for a certain pressure, it maintains that pressure within 2-3 P.S.I. every time... static or dynamic pressure!

Mark

Guys, perfect example of a PRV is the valve on the oxygen cylinder of an acetylene torch. The cylinder itself is pressurized at something like 2,000# when full. The valve takes that down to whatever you set it at, but way less than a hundred. If this idea of "it only works when fluid is being used" was correct, you would have 2,000 psi build up on the torch hoses every time you stopped using it. That simply does not happen. The PRV works whether oxygen is being drawn or not.

Absolutely agree with you Jlisenbe!