Why Is My Water Pressure Low?
One weak faucet is usually a local fix. Low pressure everywhere points to a supply or pipe problem. Here is how to tell.
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- One fixture
- Often a local fix
- Whole house
- Supply or pipe issue
- Check first
- Aerator and valves
If one faucet has low pressure, the problem is usually local to that fixture, such as a clogged aerator or a partly closed valve. If pressure is low everywhere, the cause is elsewhere in the supply, such as a pressure regulator, the main valve, or a pipe issue.
If it is one fixture
- Unscrew the aerator from the faucet and clean out mineral buildup or debris.
- Check the shut-off valves under the sink and make sure they are fully open.
- Look for a kinked supply line behind the fixture.
- For a shower, clean the shower head or soak it in vinegar to dissolve mineral deposits.
If it is the whole house
- Confirm the main shut-off valve is fully open.
- Check whether a pressure-reducing valve is present and possibly failing.
- Ask neighbors whether they also have low pressure, which can indicate a municipal supply issue.
- Look for signs of a leak that could be reducing pressure.
- For well systems, check the pressure tank and pump, which may need service.
Test at different times
Pressure that drops only when several fixtures run at once can point to pipe sizing or a supply limitation rather than a single faulty part.
When to call a plumber
- Pressure is low throughout the home and simple checks do not help.
- You suspect a failing pressure regulator or well equipment.
- There are signs of a hidden leak, such as damp walls or a rising water bill.
Sources and assumptions
This guide covers common residential causes. Diagnosing supply and well systems often requires professional tools and experience.
Frequently asked questions
- Why is only my shower pressure low?
- A single low-pressure shower is usually a clogged shower head or a partly closed valve, often from mineral buildup. Clean or replace the head and check the valve before assuming a larger problem.
- Can a water pressure regulator cause low pressure?
- Yes. A failing pressure-reducing valve can lower pressure throughout the house. A plumber can test and adjust or replace it.
- Does low water pressure mean I have a leak?
- Not always, but a leak can reduce pressure. If pressure is low along with a rising water bill, damp spots, or a running toilet, investigate for a leak.