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How to Diagnose & Repair a Bad Water Pressure Regulator InspectAPedia®  -     Diagnosing a Bad Water Pressure Regulator at buildings connected to a municipal water supply How to diagnose loss of water pressure or loss of water in a building

This article describes Diagnosing a Bad Water Pressure Regulator - how to diagnose the loss of water pressure and the need for a replacement water pressure regulator. The process of water pressure problem diagnosis and the costs of the repair are explained. Readers whose building is served by a private pump and well system should see WATER PUMP PRESSURE CONTROL.

Distinguishing between static water pressure, dynamic water pressure, and water flow rate can help diagnose water problems in a building. Here we explain these concepts and we describe how to measure water pressure and flow at a property where either municipal water supply or a private well and pump water supply is in use.

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What is a Water Pressure Regulator, Where are They Installed, Why?

Causes of Variation in Building Water Pressure

The water pressure regulator setting may not be the same as the water pressure you'll actually get in the building. Depending on the size of the building, its piping size and length of piping runs, and the number of fixtures and number of occupants (and similar variables) in a building, it is possible to draw water out of the building supply piping at such a high rate that the overall building water pressure drops considerably below the pressure setting at the water pressure regulator.

With a municipal water supply the water pressure will vary depending on how many fixtures are being run, and also the municipal water system pressure may vary in the street as well. Water flow rate in a building also depends on the diameter, length, and number of bends or valves in the piping system. Clogged water pipes reduce water flow rate, not water pressure.

With a private well and pump water supply, water pressure will also vary depending on the water pump on and off cycle and possibly on the ability of the well to deliver water.

How do we Diagnose Poor Municipal Water Pressure & Flow in a Building

Key things to check when water pressure and flow are inadequate in a building served by municipal water supply are

• The condition of individual plumbing fixtures, faucets, valves, and controls. A clogged sink or shower strainer will cause bad water pressure at individual fixtures while others may flow freely. A plumbing shutoff valve that is partly closed or clogged with debris will cause bad water flow at that fixture.
• The incoming municipal supply pressure. The municipal water supply source may be delivering water at low pressure.
• The condition of water piping between the building and the street water main. An older water supply pipe connecting the building to the water main in the street may be small in diameter, clogged with minerals, rust, or debris, or it could be leaking underground.
• The condition of building water supply piping. Clogged pipes due to minerals or rust, small diameter piping, long piping

For details about the above items, see BAD MUNICIPAL WATER PRESSURE or FLOW

• The setting of the water pressure regulator at the buliding water meter or water shutoff valve. This topic is discussed just below.

Bad water pressure regulator or bad pressure regulator adjustment: (poor municipal water pressure) if the building is connected to a municipal water supply there may be a water pressure regulator installed, usually close to the water meter or where the water supply pipe enters the building. Photos of water pressure regulators and diagnosis and adjustment advice are at WATER PRESSURE REGULATOR ADJUST.

If the pressure control was set too low to start with or if there is a problem with the water pressure regulator, you may see an improvement in water pressure by diagnosing and adjusting or repairing this control.

If the loss of water pressure was sudden, it's not likely to be a problem the pressure regulator except in the less common cases of a blockage or failure in the regulator itself. In this photo our flashlight lights up a (rather amateurish looking) water pressure regulator installed on a municipal water supply.

You can see that a previous connection to the water meter was cut, left shut off (see that shutoff valve at the left hand vertical pipe - what happens if someone opens that valve?), and new fittings were installed to conduct incoming water to the building water supply piping.

The use of smaller diameter flexible copper tubing might restrict the incoming water flow, but the presence of a pressure regulator at all suggests that the incoming pressure may have been excessive. (Too high water pressure leads to fixture leaks.)

How to Adjust the Water Pressure Regulator on Municipal Water Supply

W we've already mentioned checking and adjusting the pressure control for the water pump on a private well system - just above. But what if the home does not have it's own well - what if the building is connected to a municipal water supply?

A water pressure regulator may be installed. See the illustration at the top of this page. A device, usually a few inches across and often shaped a bit like a bell, may be found installed at the water meter. The water meter is often installed where water pipes enter the building and the pressure regulator will be installed just after the water meter on the same pipe. You may see a screw secured by a lock-nut on the top of the meter or there may be another screw or knob that will permit the water pressure regulator to be adjusted to set the water pressure up or down in the building.

Which way to turn the water pressure regulator screw? On most pressure regulators, after loosening the lock-nut around the adjusting screw, turning the screw in will increase the water pressure. Don't overdo-it. Just a turn or two should make a difference. Keep track of the number of turns so that you can go back to where you started if necessary.

Sometimes the municipal water supply may itself be temporarily shut down or running at reduced flow. Check with your local water department or neighbors.

Increasing the building water pressure by adjusting the pressure regulator (or a pump pressure control switch) will not fix a poor water delivery rate from the source (municipal water main or local private water pump), but if the pressure was set too low to start with you may see an improvement by this adjustment. If your loss of water pressure or flow was sudden, it's not likely to be a problem with the pressure regulator except in the less common cases of a blockage or failure in the regulator itself.

A Guide to Building Water Pressure by Adjusting or Repairing the Water Pump Pressure Control Switch on a Private Pump and Well Water Supply

For details about diagnosing poor well water pressure and flow, start at BAD WELL WATER PRESSURE or FLOW or go directly to the individual items listed just below.

• How to Adjust Water Pump Pressure: The detailed, step by step procedure for inspecting and adjusting the water pressure control switch is discussed in detail at ADJUST PUMP PRESSURE CONTROL.
• Diagnosing Water Pump Short Cycling on and off: If your water pump is clicking on and off too often or quite rapidly see SHORT CYCLING.
• Diagnosing & Repairing Lost Air in the Water Tank: The problem of lost air in the water pressure tank along with how to correct that condition are discussed beginning at SIGNS OF AIR LOSS.
• Diagnosing & Repairing a Water Pressure Control or Water Pump Control Switch: We discuss diagnosing and repairing a water pressure control switch that sticks "on" or "off" or simply won't operate, at water pump Pressure Switch Repairs.

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PLUMBING TOPICS
OIL TANKS
SEPTIC SYSTEMS
WATER PRESSURE & FLOW MEASUREMENT
  Definition of Static Water Pressure
  Definition of Dynamic Water Pressure
  How to Measure Water Flow Rate in a Building
WATER PRESSURE GAUGE ACCURACY
WATER PRESSURE LOSS DIAGNOSIS GUIDE
BAD MUNICIPAL WATER PRESSURE or FLOW
BAD WELL WATER PRESSURE or FLOW
  Water Pressure Intermittent
  No Water Pressure
  Well Tank relation to Water Pressure
  Shaking the Water Tank?
  Water Pressure Tank Problems
  Water Pressure Tank Diagnosis
  Water pressure Later Returns "on its own"
  Water pipe clog diagnosis
  Water pipe clog repair guide
  Making the "right" repair
  Typical Water Tank & Pump Prices
  Typical Pressure Tank & Pump Prices
WATER PRESSURE REGULATOR ADJUST
  What's a Water Pressure Regulator?
  Causes of Variation in Water Pressure
  Diagnose Poor Municipal Water Pressure
  Adjust Bad Pressure Regulator on Municipal Water
WATER PRESSURE REPAIR GUIDE & COSTS
  Questions about lost water pressure
  Advice to a homeowner
  Adjusting Water Pump Pressure Control
  Right Repair to Pump & Tank?
  Well Pump & Tank Replacement Costs
  Reliability of Pump & Tank Repairs
WATER PUMPS & WELL TANKS
WATER PUMP CONTROLS & SWITCHES
  IDENTIFY WELL PUMP TANK COMPONENTS
  MAIN WATER SHUTOFF VALVE
  WATER PUMP ELECTRICAL SWITCHES
  WATER PUMP PRESSURE CONTROL
    WATER PUMP PRESSURE CONTROL ADJUSTMENT
    WATER PUMP PRESSURE CONTROL REPAIR
    WATER PUMP PRESSURE CONTROL REPLACE
  WATER PRESSURE REGULATOR ADJUST
  WATER PUMP RELAY SWITCH
  WATER TANK AIR VOLUME CONTROLS
  TANK AIR INLET VALVE
  TANK AIR VALVE REPAIRS
  WATER TANK PRESSURE GAUGE
  WATER TANK DRAIN VALVE
  WATER TANK RELIEF VALVE
  CHECK VALVES
  WATER FILTERS
WATER PUMP TYPES & LIFE EXPECTANCY
WATER PUMP & TANK SAFETY
WATER SUPPLY & DRAIN PIPING
WATER TANK TYPES: WATER, OIL, EXPANSION, ALL
WATER TANK LIFE EXPECTANCY
WATER TANK REPAIRS
  CONTROLS & SWITCHES on WATER TANKS
  INTERMITTENT CYCLING WATER PUMPS
WATER TANK AIR, HOW TO ADD
WATER TANK BLADDERS & CAPTIVE AIR
WATER TANK REPLACEMENT
WATER TANK BLADDER PRESSURE ADJUSTMENT
WATER TANK PRESSURE CALCULATIONS
WATER TANK SIZE & VOLUME
WATER TANKS HOW THEY WORK
WATER TESTING
WATER TREATMENT EQUIPMENT CHOICES
WELLS CISTERNS & SPRINGS
WELL LIFE EXPECTANCY
WELL PUMP TYPES & LIFE EXPECTANCY

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