Water Pressure Reducing Valves - FAQ
- What is a Water Pressure Reducing Valve?
- What is Water Pressure?
- What is Wrong with High Water Pressure?
- Does High Water Pressure Cause "Water Hammer?"
- What is the difference in water flow from a fixture when the pressure is at 100 lbs. vs. a pressure of 50 lbs.?
- Are there any studies to support this savings figure?
- Where are Water Pressure Reducing Valves most commonly used?
- Why do we now call Water Pressure Reducing Valves "Primary Conservation Controls"?
- How do Water Pressure Reducing Valves save water?
- How much does a typical family of four use?
- How do Water Pressure Reducing Valves affect the wastewater system?
- How do Water Pressure Reducing Valves save on energy?
- How do these savings benefit the water and energy utilities?
- How do Water Pressure Reducing Valves save on maintenance?
- Do codes require Water Pressure Reducing Valves?
- How long will a Water Pressure Reducing Valve last?
- If I install a Water Pressure Reducing Valve, what savings can I expect?
- Should we consider using other water and energy conservation devices?
- Do flow-restricting devices actually save water?
- What are some tips the user can employ to save water and energy?
- What does a Water Pressure Reducing Valve cost?
- How do I know if I have high water pressure?
- How can I get a Water Pressure Reducing Valve installed?
1. What is a Water Pressure Reducing Valve?
Also called water pressure regulators, water pressure reducing valves are compact, inexpensive valves that perform two functions:
- They automatically reduce the high incoming water pressure from the city mains to provide a lower, more functional pressure for distribution in the home.
- They "regulate" by maintaining a set pressure in the home usually 50 lbs. 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 can erode or wear away many materials. A big "push" in home plumbing can also cause leaking water heaters, banging water pipes, dripping faucets, dishwasher, and clothes washer noise and breakdown, or leaking water pipes. 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, probably most important to the average homeowner is that it can add to the cost of water, energy, and waste water bills.
4. Does High Water Pressure Cause "Water Hammer?"
Yes, and water hammer is very simply the noise generated by the shocks of high-speed water flowing in a pipe when a fixture is suddenly closed. The sudden 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 comparable 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 principle is 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 lbs. vs. a pressure of 50 lbs.?
Reducing the pressure from 100 lbs. to 50 lbs.will result in a savings of approximately 1/3 because 1/3 less water flows at this lower pressure. Remember, there is more "push" behind the water at 100 lbs. than at 50 lbs. and most of this water is wasted. Almost twice as much water flows at 150 lbs. than 50 lbs., most of which is wasted. Moderate savings would result if your supply pressure was 65 lbs. However, even at this lower pressure, savings with a water pressure reducing valves 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 reducing valves. It is interesting to note that their report concluded that in test locations using water pressure reducing valves, there was a water consumption reduction of 30% in October and November and 37% in December.
7. Where are Water Pressure Reducing Valves most commonly used?
Water pressure reducing valves 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 Water Pressure Reducing Valves "Primary Conservation Controls"?
Most people have considered water pressure reducing valves 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 in addition to cost problems, water pressure reducing valves have become increasingly more important because they automatically provide the advantage of conserving water and energy.
9. How do Water Pressure Reducing Valves save water?
As mentioned before, 1/3 less water flows 50 lbs. than at 100 lbs. Therefore, when you reduce the city main pressure to a more moderate pressure of 50 lbs., you can look forward to conserving up to 1/3, or more, of the water previously consumed and 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 for interior plumbing. 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. If you have teenagers, you would undoubtedly use more than the above averages.
11. How do Water Pressure Reducing Valves affect the wastewater 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 water pressure reducing valves save 1/3 of the metered water, they also contribute to saving up to 1/3 of the wastewater, which 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 Reducing Valves save on energy?
The Environmental Protection Agency estimate that 30% of the water used in households is heated and, in order to heat this water, it takes energy. If a water pressure reducing valve 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, 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 the extra gallons, the water purification plant didn't have to treat it, while the building itself saved on pumping of 3,000,000 gallons, resulting in 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 Water Pressure Reducing Valves save on maintenance?
We have previously described the effects of high water pressure on piping and appliances. When having these appliances work under a lower pressure, their life expectancy will be much longer and 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 be resulting.
15. Do codes require Water Pressure Reducing Valves?
Yes. They are required by the Federal Housing Administration, the regional plumbing codes such as IPC and UPC, and numerous city and state codes. The requirement is that whenever the city main water pressure exceeds 80 lbs., a water pressure reducing valve must be installed. However, because of the recently acknowledged advantages of water pressure reducing valves conservation wise, they could be economically installed even where supply pressures are in the vicinity of 60 lbs. because of the water and energy saving benefits they can provide.
16. How long will a Water Pressure Reducing Valve last?
Water Pressure Reducing Valves have been described as "life-of-mortgage" products, because historically a malfunctioning water pressure reducing valve 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 and actually it is no more difficult to repair a water pressure reducing valve than it is to fix the kitchen faucet.
17. If I install a Water Pressure Reducing Valve, what savings can I expect?
An average savings would be from $50 to $150 per year, probably much higher. Based on the fact that 1/3 less water flows at 50 lbs. than 100 lbs., you can expect to save up to 1/3 of the water previously consumed. As a typical family of four uses 90,000 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.) 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. 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 will not be assessed on that. (Contact your local authority for any assessment charges.) 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 reducing valve is the hub of a conservation program; but you should also consider flow control devices, low-flush toilets, improved water heating equipment, and better disciplined habits by the user. However, if none of these devices were installed, the water pressure reducing valve would still serve to contribute important and significant savings in energy and water, resulting in 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 heater boilers. Many showerheads, for example, apply water at a rate of 6gpm. Applying a 3gpm 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 lbs. and operating under a higher pressure will permit greater flow. That's why we say a water pressure reducing valve is the "hub" of a program because it maintains a constant pressure throughout the home, thereby improving the performance of flow-restricting devices.
20. What are some tips the user can employ to save water and energy?
- Put a stopper in your sink or use a dishpan when you wash dishes.
- Washing with running water uses 30 gallons per meal.
- Keep a bottle of drinking water in the refrigerator running the water from the faucet until cold will waste a gallon.
- Wait until you have a full nine-pound wash before you run your washing machine. The average machine uses 50 gallons per load.
- 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.
- 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.
- Don't use the toilet bowl to dispose of cigarette ashes, facial tissues, and other materials. A normal flush requires 8 gallons.
- Use dishwasher only when completely full.
- Fix dripping faucets promptly. Nearly two gallons can be wasted per day of dripping.
- Running toilets can waste four gallons per hour. Keep them in good repair.
- THINK before you turn on the tap.
21. What does a Water Pressure Reducing Valve cost?
There are, of course, different styles of water pressure reducing valves 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.
22. 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, your local plumbing contractor or utility can test your pressure with a gauge.
23. How can I get a Water Pressure Reducing Valve installed?
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 types of water pressure reducing valves available and the one best suited for your home. Although water pressure reducing valves are fairly simple to install and could be a do-it-yourself project, there are some laws which mandate that only a licensed plumbing contractor be permitted to work on the home potable drinking water system for health and safety purposes.