Presure Reducing Valves

PRESSURE REDUCING VALVES

What is a Water Pressure Regulator?

Also called water pressure reducing valves, they are compact, inexpensive devices that perform two functions:

(1) they automatically reduce the high incoming water pressure from the city mains to provide a lower, more functional pressure for distribution in the home

(2) they “regulate” by maintaining a set pressure in the home usually 50 psi — thereby insuring that the home piping and appliances operate under a safe, more moderate, but satisfactory pressure.

What is water pressure?

When a fixture in a home is opened and water flows from it, it is because the water is “pushed.” This “push” is pressure. The speed at which water flows from the opened outlet depends on the amount of “push” or pressure which exists at that time in the system. In short, the higher the pressure, the stronger the “push” behind the water.

What is wrong with high water pressure?

High water pressure, which is generally considered anything above 60 lbs., has some advantage, such as in firefighting systems. However, in the home plumbing system, it can be damaging because water, with a strong “push” behind it, can erode or wear away many materials and cause water heaters to leak, banging water pipes, dripping faucets, excessive dishwasher and clothes washer noise and breakdown, and leaking water pipes. Therefore, water flowing at a rate in excess of that necessary to satisfy normal fixture or appliance demands becomes damaging, wasteful and reduces the life expectancy of equipment in the system. But, most important to the average homeowner is that high water pressure can add to the cost of water, energy and waste water bills.

Does high water pressure cause “water hammer”?

Yes. Water hammer is simply the noise generated by the shocks of high-speed water flowing in a pipe when a fixture is suddenly closed. This abrupt stoppage causes a “bounceback” of the water and is called water hammer, causing banging pipes, noisy systems and damage to appliances. It might be compared to driving your car at slow speed into a wall where the effect is negligible. However, if you drove the car at a much higher speed, the impact would be greater and, consequently, so would the bounceback or shock. Another description of the water hammer effect of high water pressure can be easily demonstrated. First, walk around a sharp corner and then run around the same corner. We can equate walking around the corner to a lower, more functional, controlled water pressure. However, when you run around the corner, the momentum forces your body to swing in a wider, uncontrolled arc. This principles based on the fact that moving objects, and this includes water, tend to move in a straight line. They resist changes in direction. Therefore, in a home where the piping has many changes in direction, water hammer shock can be limited by reducing the water pressure.

What is the difference in water flow from a fixture when the pressure is at 100 psi vs. a pressure of 50 psi?

Reducing the pressure from 100 psi to 50 psi will result in a saving of approximately 1/3 because 1/3 less water flows at this lower pressure. Remember, there is more “push” behind the water at 100 psi than at 50 psi and most of this water is wasted. Note the illustration where almost twice as much water flows at 150 psi than 50 psi, most of which is wasted. A moderate savings would result if your supply pressure was reduced to 65 psi However, even at this lower pressure, savings with a regulator would be 20%.

Are there any studies to support this savings figure?

Yes. In 1971 the Washington Suburban Sanitary Commission conducted a test program in 2,400 dwelling units that has attracted widespread interest from more than 40 states and various foreign countries. One of the devices used in their conservation study was a water pressure regulator. It is interesting to note that their report concluded that in test locations using regulators, there was a water consumption reduction of 30% in October and November and 37% in December.

Where are Water Pressure Regulators most commonly used?

Water pressure regulators are commonly installed at the meter in residential, commercial and industrial buildings. This location is desirable because it then controls the water pressure flowing to all appliances and outlets within the building and provides an inexpensive means of supplying lower, more functional water pressure to outlets and appliances.

Why do we now call Regulators “Primary Conservation Controls”?

Most people have considered regulators as pressure controls because, as described in the foregoing, they are used to protect appliances and piping from the effects of high water pressure. However, because of water and energy shortage and cost problems, regulators have become increasingly more important because they automatically provide the advantage of conserving water and energy.

How do Regulators save water?

As mentioned before, 1/3 less water flows at 50 psi than at 100 psi Therefore, when you reduce the city main pressure to a more moderate pressure of 50 psi, you can look forward to conserving up to 1/3, or more, of the water previously consumed. This will be reflected on your water bills.

How much does a typical family of four use?

A typical family of four uses an average of 255 gallons of water each day. This is broken down by: dishwashing – 15 gallons; cooking/drinking – 12 gallons; utility sink – 5 gallons laundry – 35 gallons; bathing – 80 gallons; bathroom sink – 8 gallons; toilet – 100 gallons. When you multiply this by a year, typical family usage totals 93,000 gallons of water. Your family particularly if it includes teenagers, would undoubtedly use more than the above averages.

How do Regulators affect the waste water system?

When we can save 1/3 of the water previously consumed, this also represents a similar saving of water which will not be going into the sewer system where it has to be treated. Water does not evaporate after we use it and it has to be piped to the wastewater system. Many sewer bill taxes or surcharges are based on the amount of water you use, with the assumption that this water is going into the wastewater system. This is billed to you as a sewer surcharge and, in many cases, the sewer tax can equal the water cost. Therefore, when pressure regulators save 1/3 of the metered water, they also contribute to saving up to 1/3 of the wastewater load and this is extremely important because it benefits both the user, by a lower sewer bill, and the community, as this is water they do not have to treat.

How do Water Pressure Regulators save on energy?

The Environmental Protection Agency estimates that 30% of the water used in households is heated. In order to heat this water, it takes energy. Logically, therefore, if a pressure regulator can reduce consumption by 1/3, we automatically cut down on the amount of hot water we’re using in lavatories and showers and, therefore, it follows that we automatically reduce the amount of energy required to heat that load. Thus, it can be easily seen that water conservation has a direct relationship to energy conservation. An average shower, for example, costs approximately 17 cents in energy and a shave with the faucet running cost 10 cents in energy.

How do these savings benefit the water and energy utilities?

A high rise office building in Chicago was designed using water conservation products which resulted in savings of more than 3,000,000 gallons of water per year. This is significant in that the municipal water utility did not have to pump that extra gallonage, the water purification plant didn’t have to treat it, the building itself saved on pumping of 3,000,000 gallons, and there must have been significant savings in energy by conserving hot water. Also, there were further savings by the fact that 3,000,000 gallons of water, or the normal portion thereof, did not have to be distributed to the wastewater system and consequently the water treatment plant did not have to retreat this water. The heating of water takes energy and it should also be remembered that “pumping” water from one place to another also requires a considerable amount of energy.

How do Regulators save on maintenance?

We have previously described the effects of high water pressure on piping and appliances. By having these appliances work under a lower pressure, their life expectancy will be much longer. Use of lower pressure will also cut down on service calls caused by problems with dish washers and clothes washers, leaky water heaters, leaking water pipes and the potential water damage which could result.

Do codes require Water Pressure Reducing Valves?

Yes. They are required by the Federal Housing Administration, the regional plumbing codes such as IAPMO, and BOCA, and numerous city and state codes. The requirement is that whenever the city main water pressure exceeds 80 psi, a regulator must be installed. However because of the recently acknowledged advantages of regulators conservation wise, regulators could be economically installed even where supply pressures are in the vicinity of 60 psi because of the water and energy saving benefits they can provide.

If I install a Pressure Regulator, what savings can I expect?

An average savings would be from $50 to $150 per year, probably much higher.

A. Based on the fact that 1/3 less water flows at 50 psi than 100 psi, you can expect to save up to 1/3 of the water previously consumed. As a typical family of four uses 93,000 gallons per year, that would mean a savings of approximately 30,000 gallons of water. The higher the pressure, the higher the savings. Lower pressures result in less savings. (Your water Co. can provide the rate.)

B. Remember also, however, that 1/3 of the water used in homes is heated; so 1/3 of the 30,000 gallons of water saved divided by 2 to reflect a cold water mixing factor would mean a savings in heating up to 5,000 gallons of hot water per year. If you figure 4 cents to heat a gallon of water, the savings would be $200.00.

C. You can also figure on a savings in your sewer surcharge bill, since most of the 30,000 gallons of water saved will not be going into the wastewater system. Therefore, you would not be assessed for that disposal. (Contact your local authority for any assessment charges.)

D. You would also have to figure the savings generated by not having to have appliances repaired or replaced more frequently. This is a nebulous figure but, based on your own experience over the past years, you could look for a reduction in the frequency of maintenance and certainly for an improved performance by these appliances.

Should we consider using other water and energy conservation devices?

Certainly. The water pressure regulator we’re talking about today is the hub of a conservation program; but you should also consider other flow control devices, low-flush toilets, improved water heating equipment and better disciplined usage habits. However, if none of these other devices were installed, the water pressure regulator would still serve to contribute important and significant savings in energy and water. This would provide an average savings of anywhere from $50 to $150 per year, or more depending on your local rates.

Do flow-restricting devices actually save water?

Yes, and they can effectively be installed on showerheads, fixtures and tankless heaters and boilers. Many showerheads, for example, supply water at a rate of 6 gpm. Applying a 3 gallon per minute flow restrictor will cut the flow in half providing savings in water and energy. It should be remembered however that their capacity is based on a “fixed” supply pressure like 50 psi and operating under a higher pressure will permit greater flow. That’s why we say a water regulator is the “hub” of a program because it maintains a constant pressure throughout the home, thereby even improving the performance of flow-restricting devices.

What are some tips the user can employ to save water and energy?

1. Put a stopper in your sink or use a dishpan when you wash dishes. Washing with running water uses 30 gallons per meal.

2. Keep a bottle of drinking water in the refrigerator — running the water from the faucet until cold will waste a gallon.

3. Wait until you have a full nine-pound wash before you run your washing machine. The average machine uses 50 gallons per load.

4. Turn the hot water off while you shave, and turn the cold water off while you brush your teeth. Shaving with a running faucet uses about 20 gallons.

5. Take showers instead of baths. The usual bath requires 36 gallons, the usual shower, only 25. Ten gallons is enough for a shower if you turn it off while you lather.

6. Don’t use the toilet bowl to dispose of cigarette ashes, facial tissues, and other materials. A normal flush requires 5 – 8 gallons.

7. Use dishwasher only when completely full.

8. Fix dripping faucets promptly. Nearly two gallons can be wasted per day of dripping.

9. Running toilets can waste four gallons per hour. Keep them in good repair.

10. THINK before you turn on the tap.

NOTE: Tips provided through courtesy of Plumbing Manufactures Institute.

How do I know if I have high water pressure?

A rule of thumb is: If you hear banging pipes in your home or observe water splashing in your sink, you probably have excessive pressure. However, for a precise reading Pink Plumbers and Sewer can test your pressure with a gauge.

How can I get a Water Pressure Regulator installed?

The easiest way would be to call Pink Plumbers and Sewer, who can provide you with an estimate and also advise of the various type regulators available and the one best suited for your home.