How to Diagnose & Repair Building Water Pressure Regulators & Water Pressure Reducing Valves
WATER PRESSURE REDUCER / REGULATOR home - CONTENTS: How to diagnose & fix a Bad Water Pressure Regulator at buildings connected to a municipal water supply - What are water pressure reducing valves, how do they work, and why are they needed? What's a Water Pressure Regulator? - How proper installation of pressure reducing valves actually improves building water pressure and flow. Direct-Acting Pressure Reducing Valves. Regulate High Incoming Water Pressure. How to Select Proper Pressure Reducing Valve. What are Wire Draw Leaks at Pressure Reducers? Reasons to use Parallel Pressure Reducing Valves. Using Expansion tanks to relieve high pressure. How to Diagnose Poor Municipal Water Pressure. Water Pressure Regulator Test, Repair
Water pressure regulator controls:
This article describes how to diagnose & repair a bad water pressure reducing valve or water pressure regulator that can result in either building water pressure and flow that are too weak, or building water pressure that is dangerously high. Distinguishing between static water pressure, dynamic water pressure, and water flow rate can help diagnose water problems in a building.
What is a Water Pressure Regulator or Pressure Reducing Valve, Where are They Installed, Why?
What's the difference between a water pressure regulator valve and a water pressure reducing valve?
Looking over water safety and flow control products offered by Watts, that company lists a range of low pressure regulators and a wide range of high capacity water pressure reducing valves.
We notice that in low pressure regulation applications such as on steam heating systems and on residential water supply systems, control valves are referred to as low pressure regulators (Watts 123LP low water pressure regulator for example - sketch at left).
Series 123LP Low Water Pressure Regulators are used in residential and point-of-use applications to regulate water pressure in piping systems that require low pressure regulation. ... Maximum Working Pressure: 200psi (13.8 bar), Adjustable Pressure Range: 10 to 30psi (69 to 207 kPa), Reduced Pressure Setting: 25psi (172.4 kPa).
Most of the pressure regulators we see listed refer to low pressure applications on steam systems, residential water systems, or fuel oil systems.
Ligher capacity water pressure reducing valves are used in commercial or industrial applications (and some residential applications) where it is necessary to protect the building plumbing system (pipes, water heater tanks, relief valves, etc). from high incoming water pressures and also to conserve water usage.
(Watts LF223 lead-free high capacity water pressure reducing valves, for example - sketch at left).
Series LF223, LF223S Lead Free* High Capacity Water Pressure Reducing Valves are used in commercial, industrial, and institutional applications to reduce incoming water pressure for protection of plumbing system components and to reduce water consumption.
It consists of a Lead Free* brass body construction (2 1/2 in. is iron), enlarged diaphragm, spring cage and seat orifice for super capacity, sealed spring cage for waterworks pit installations and an optional thermal expansion bypass. ... Maximum Working Pressure: 300psi (21 bar), Adjustable Reduced Pressure Range: 25 to 75psi (172 to 517 kPa), Standard Pressure Setting: 50psi (345 kPa).
Watts and other manufacturers produce a wide range of types of water pressure regulators and water pressure reducing valves to handle fluid types, operating pressure ranges, and also responsiveness where the drop in reduced pressure should be kept to a minimum even as the water volume demand varies widely.
An example of a commercial grade high capacity water pressure reducing valve, the Watts Model 127W is shown at left.
In our articles we use the terms water pressure regulators and water pressure reducing valves interchangeably as referring to devices that both regulate the pressure or flow of water from a supply source into a building, and (if high water pressures are present) protect building plumbing systems from excessive water pressure damage by reducing incoming high water main pressure (that can be more than 150 psi in some communities) to a safe level (typically 50 psi) in the building.
OPINION: even after you've seen these two prototypical sketch of a low pressure water regulator and a higher-capacity water pressure reducing valve, in the field, rather than guess which water pressure operating range was intended by the device you're looking at, look for a model number or part number instead.
Why are water pressure regulators installed on water supplies? Often municipal water supply pressure can run quite high, say over 80 psi and in some communities, more than 150 psi.
Our photo (left) shows typical incoming municipal water piping at a building. From left to right we see a main water shut off valve, a water meter (wires lead to an outdoor water meter reading device), a water pressure regulator, and water piping rising into the building.
This high pressure would cause leaks at many ordinary residential plumbing fixtures like sink and tub faucets or toilets, as well as some actually dangerous conditions - see WATER PRESSURE TOO HIGH: DANGERS. So where city or municipal water supply pressures exceed 80 psi, the building should have a pressure reducing valve, also referred to by some as a water pressure regulator installed, usually right after the water meter where water enters the building.
Building Code Requirement for Pressure Reducing Valves
In fact most national and local plumbing codes require that a water pressure reducing valve should be installed at buildings where municipal water supply pressures (in the water main in the street) exceed 80 psi. Excessive water pressures can burst pipes, cause dripping faucets, and can even cause rupture and explosion of both cold water pressure tanks and hot water storage tanks.
Importance of Selecting the Proper Pressure Reducing Valve
If your building already has a water pressure reducer installed, it may be defective or it may be set too high, or the wrong model pressure regulator may be installed.
If the wrong pressure reducing valve model is installed it may not be operating at the water pressure range and flow rates for which it was designed.
The result can be poor performance, noisy plumbing, poor water flow at least at times, not enough water pressure under high-draw conditions, or Wire Draw Leaks at Pressure Reducers and even dangerous building conditions or risk of building leaks and flooding under low water flow conditions. A more complete catalog of high water pressure problems is found
at WATER PRESSURE TOO HIGH: DANGERS.
Variations in building occupancy levels: Where building demand for water flow varies widely, a single pressure reducing valve may not be able to handle the maximum water demand flow rate.
This condition occurs at buildings where there is a large water supply main to an apartment or office building whose water demand can vary enormously (0.5 gpm to 100 gpm) depending on the building occupants. Watts and other pressure reducing valve producers recommend a nice solution to this problem (Image at left, courtesy of Watts Controls).
As Wattsand other manufacturers suggest, parallel pressure reducing valves are sometimes installed to correct this difficulty. One pressure regulator control is set at a higher psi flow rate than the other.
Visit our website https://ringhotwater.com.au/ for more information.
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Visit our website https://ringhotwater.com.au/ for more information.
Submitted on: 2016-12-13 12:06:57