The following information was prepared by WATTS REGULATOR COMPANY
Questions and Answers about Water Pressure Reducing Valves
• Save WATER
• Save ENERGY
• Save WASTEWATER
• Save MAINTENANCE
Water Pressure Reducing Valves Conserve Both Energy and Water “Automatically”.
The following information will familiarize you with water pressure reducing valves, also typically called regulators. It will emphasize that regulators are not only water pressure controls but are actually "primary conservation controls" which automatically conserve water and energy when used in high pressure areas.
The supply of water and energy is one of our most critical national problems. If we cannot increase our supply, then it is imperative to reduce our consumption. Fortunately it's been proven that we can conserve dramatically and in a manner which will not seriously affect the lifestyles we have become used to. Water and energy conservation are so intimately intertwined that they are practically synonymous. Any reduction in the usage of water will automatically result in a reduction of the use of energy. What this means, therefore, is that our whole philosophy on the use of water is changing and we are finally recognizing that we have been
"water rich" over the years and it is now time to get back to reality by adjusting to our actual needs and to practice good conservation principles.
The purpose of this information is to acquaint you with a simple way to conserve water and energy. The hub of the program is the use of water pressure reducing valves (regulators), an automatic control which is installed at the water service in homes and other buildings to reduce the city main's pressure to a lower, more functional pressure (for most purposes 50 psi water pressure is adequate.) Regulators are simple inexpensive products that have a pay-back period of anywhere from 6 months to 12 months. As you will see on the following pages, they can save between 30,000 and 40,000-gallons of water per year in the average home alone. If these savings were applied to 1,000,000 typical homes throughout the country, consider the tremendous impact this would have on our national conservation goals. Thus, water and energy conservation, through the use of water pressure reducing
valves (regulators), is not only in the national interest but provides a significant benefit to the homeowner, the local water purveyor and energy utility as well. The higher the water pressure, the greater the amount of water that is wasted. (See question 5 for detailed explanation.)
1 - 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.
2 - 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.
3 - 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.
4 - 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 “bounce back” 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 bounce back 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.
5 - 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%.
6 - 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.
7 - 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.
8 - 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.
9 - 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.
10 - 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.
11 - 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.
12 - How do Water Pressure Regulators save
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.
13 - 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.
14 - 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.
15 - Do codes require Water Pressure
Yes. They are required by the Federal Housing
Administration, the regional plumbing codes such as
IAPMO, Southern Building Code, 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.
16 - How long will a Regulator last?
Regulators have been described as "life-of-mortgage" products, because historically a malfunctioning
pressure regulator is not replaced but simply cleaned
or repaired via an inexpensive service kit. Design
wise, it is similar to the kitchen faucet in that dirt or
foreign matter on the seating area can cause problems. Actually it is no more difficult to repair a regulator than it is to fix the kitchen faucet. (Please note that this is based on a national average. Arizona has harsher water which reduces the life expectancy of plumbing items, such as PRV's.)
17 - 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 company 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
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.
18 - 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.
19 - Do flow-restricting devices actually save water?
Yes, and they can effectively be installed on showerheads, fixtures and tankless heaters in 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
20 - 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
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
21- What does a Water Pressure Regulator cost?
There are, of course, different styles of regulators
and various installation charges throughout the
country. An estimate can be obtained from your
local qualified plumbing contractor. To determine
how much you, as an individual, would be saving,
it would be necessary to consider the factors in
question 17, in comparing with your current water
and energy bills. See below for examples.
22 - How do I know if I have high water
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, your local plumbing contractor or
utility can test your pressure with a gauge.
23 - How can I get a Water Pressure
The easiest way would be to call your local qualified
plumbing contractor who can provide you with an
estimate and also advise of the various type regulators available and the one best suited for your home.
Although regulators are fairly simple to install and
could be a do-it-yourself project, there are some laws
which provide that only a licensed plumbing contractor be permitted to work on the home potable drinking water system for health and safety purposes.
HOW TO FIGURE YOUR
(Refer to your annual water and energy
bills for your specific rates and usage)
1. WATER BILLS
Cubic Feet of Water x Rate = Total Bill
15,000 Cubic Feet x $ .90 P/C Cu. Ft. =
(Approx. 112,000 Gallons)
SAVINGS with Regulator -1/3 or
5,000 Cu. Ft. @ $ .90 P/C Cu. Ft.
2. SEWER ASSESSMENT
Cubic Feet of Water x Rate = Total Bill
15,000 Cubic Feet x $ .90 P/C Cu. Ft. =
SAVINGS with Regulator -1/3 or
5,000 Cu. Ft. @ $ .90 P/C Cu. Ft.
3. ENERGY COST (Approximately 1/3 of total water used is heated.)
Gallons Water Heated
2 x $ .02 P/Gal.
37,000 Gal. x .5 = 18,500 x $ .02 = SAVINGS with Regulator - Approx. 1/3 or 12,000 Gal. with additional adjustment factor of
1/2 = 6,000 gal.
Actual Maintenance Bill
One "high-pressure" related service call @ $50.