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6 Common Causes of Low Water Pressure

Evergreen Plumbing & Mechanical

Problems with water pressure can be frustrating. It can take seemingly ages to fill a bathtub or sink. The showerhead trickles when what you need is a jet of high-pressure water. Plus, the washing machine and dishwasher take an extended amount of time to run a cycle.

There could be a variety of reasons for low-water pressure. Below are some of the most common causes. Some of these you can fix yourself. Others will require a professional plumber to diagnose and resolve. Either way, you want to solve your water-pressure woes as soon as possible.

Low water pressure can be frustation, whether in the shower, cleaning dishes, or simply washing your hands. But there are a few common causes of low water pressure, which you'll can identify and troublehsoot by diving into the info below.

Before diving into the details below, here's a quick overview of why your water pressure is low:

  • Any one of your fixtures is leaking or clogged
  • Your water meter or main shutoff valve is partially closed
  • Your pressure regulator is faulty, causing fluctuations
  • Old pipes like galvanized steel corrode, lowering water pressure
  • Your water heater, which affects pressure, is broken
  • Hardwater is causing calcium accumulation, slowing water flow

The Fixture is at Fault

If only a single fixture has low water pressure, you likely have something wrong with the fixture itself or the plumbing attached to it. This could be something as simple as a clog or the problem could be more severe such as a leak.

A Valve is Partially Closed

Either the water meter valve or the main shutoff valve is partially closed.

Located next to a home's water meter is the water meter valve. Most people will never use this valve. It technically belongs to the local water company. This valve should only be used by water company personnel. If the water pressure is low throughout the home, it’s possible this valve has not been fully opened. This is commonly the case after work has been done on a home's plumbing system. This valve is located outside of a house. The valve's handle should be parallel with the water pipe. If the handle is at an angle, it’s not completely open.

A home's main shutoff valve can often be found inside a home near the main supply pipe. Make certain the valve is completely open. The main shutoff valve should be turned completely in a counterclockwise direction if it has a wheel-like handle. Some are a lever handle. In this case, it’s fully open when the handle is parallel to the pipe direction.

Faulty Pressure Regulator

This is also known as a pressure-reducing valve. It’s designed to maintain a safe level of pressure so a home's pipes will not be damaged. It’s possible this device is failing, causing an increase in water pressure or a sudden significant drop water pressure.

Old Pipes

Old pipes are made of galvanized steel and corrode to the point that water flow is significantly decreased. These types of pipes will corrode on the inside, so damage isn’t visible without specialized video equipment. The corrosion and scale will build up over time and increasingly restrict the flow of water. The only solution could be to repipe the home's plumbing system.

Broken Water Heater

This can be determined by running the hot water and cold water at each faucet. When only the hot water has problems with pressure, it’s likely the issue can be traced to the water heater.

Hard Water

If your water is high in mineral content, you have hard water. Not only does it leave unsightly scale deposits on plumbing fixtures, such as the showerhead, but hard water can also cause a buildup of calcium in pipes to the point that it constricts the flow of water. A water softener can help solve this problem.
Bottom line: When anyone notices the water pressure in their home is low, it is a legitimate cause for concern. Evergreen Plumbing and Mechanical is happy to help diagnose your plumbing system. To schedule an appointment, call 503-714-7004.