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Most of us have been there before. We head to the kitchen or bathroom sink and turn on the tap only to find that water is barely trickling out. This can be concerning for even the most experienced homeowners, renters and DIYers. But the cause of low water pressure in the house isn’t always a broken pipe or something catastrophic.
This guide will explain some of the most common causes for low water pressure, as well as what to do about them.
How to Identify Low Water Pressure
Most of the time, identifying low water pressure is very easy because it’s all of a sudden. However, there may be instances where water pressure drops slowly over time, going unnoticed or making a homeowner feel like they’re tricking themselves into thinking there is an issue. However, there is an easy way to test water pressure for most homes using a test gauge.
Head outside to the water spigot and remove the hose. Screw the test gauge onto the spigot ensuring that the face of the gauge is visible. Turn the spigot valve on and check the reading. This will indicate the amount of pressure coming into the home from the city or well. Record the reading and compare it to future readings performed whenever water pressure feels different (lower or higher).
There is another use for this gauge. Users can locate leaks within their system by installing the gauge, leaving all of the valves shut and water-using appliances like ice makers, dishwashers and washing machines off and closing the main water valve to the house. If the pressure is consistent over an hour or so, the home’s plumbing is likely leak-free. If it drops more than three PSI or so, there may be a leak.
Reasons for Low Water Pressure
There are many reasons why a home’s water pressure may drop, whether it be all of a sudden or over time. The reasons listed below are some of the most common causes of low water pressure in a house.
1. Water Main Break
If the water pressure in the entire house drops all at once, there may be a water main break in the system. This happens often in cold weather or when older systems are in need of upgrading. It may cause flooding in the street and yards nearest to the break, or it may take the municipality a while to find it. In any case, it’s likely that the entire neighborhood’s water pressure is low, so ask the neighbors.
2. Well Failure
Many folks whose homes are on wells are in constant fear of them failing, and that’s because they very well can. If the pressure in the home dropped, the well pump may not be running. This could be because the breaker tripped, the motor failed or the aquifer itself ran dry.
3. Main Valve Is Slightly Closed
If water pressure feels low throughout the whole house, but the water is still flowing, it could be the main valve. This valve controls the flow of water from the city or well, and it’s usually found inside the home where the main line comes in (there may be two valves if the city installed a meter). These valves may accidentally be shut by someone in the basement, or they may fail over time.
4. Pressure Regulator Is Broken
There is a device installed on most main water lines called a pressure regulator. This regulator prevents water pressure from spiking in the home (usually no more than 40 to 60 PSI). Most regulators are adjustable, so it may be that the regulator is set too low. They can also become clogged with sediment over time.
5. City Is Flushing Hydrants
Cities and water companies have to flush hydrants regularly to guarantee that they’re working properly and aren’t filled with build-up and mud. When they flush these hydrants, they let hundreds of gallons flow each minute (some can be up to 1,500 gallons), and they do so for several minutes at a time per hydrant. This can cause water pressure to temporarily drop for homes on the same loop.
6. Leak in the House
If the water pressure feels lower than it used to be, it could be because the pipes sprung a leak. Common places for leaks are around the water heater, flexible hoses and valves under sinks. However, leaks can happen in walls, and if they’re caused by frozen pipes, they can cause a serious mess quickly.
7. Clogged Screen in the Aerator or Shower Head
There are small screens in sink aerators and shower head fixtures, and their job is to collect sediment while also dispersing water effectively. If there is a lot of sediment in the water, these screens can close off completely, dropping water pressure to almost nothing.
Sediment can also clog a toilet fill valve. While there aren’t any screens, the build-up can restrict water flow and prevent the toilet from filling effectively.
8. Water Heater Issue
If the water pressure is only low on the hot water, there’s a problem with the water heater. It could be that the water heater is leaking, became clogged with sediment, or the valves aren’t fully open.
How to Fix Low Water Pressure
Fixing low water pressure can be simple and inexpensive or complicated and costly. Here are some of the most common ways to fix low water pressure.
Call the City
There is a chance that the water pressure is low because of the city. Whether it’s a water main break, hydrant flushing or they’ve shut the system down for repair, the city should be able to explain if the issue is theirs or yours.
Open or Replace Valves
If there are any valves throttled back, it’s a good idea to open them. This will allow more water volume to flow through the valve, ultimately increasing the pressure at the sink, shower, toilet or appliance.
If a valve is completely closed, it’s a good idea to figure out exactly what that valve does before opening it. This can help avoid flooding or damaging the home.
If a valve is leaking or broken, it’s important to fix it as soon as possible. This valve may cause restricted flow, but if the internal parts break loose, they could cause the whole system to clog.
Clean Aerators and Screens
Another way to fix low water pressure is to clean the screens inside the sink aerators and shower heads. Simply unscrew the aerator from the shower head, remove the rubber washer with a pick and dump the screen onto a piece of paper towel. Use a stiff brush to remove any build-up on the mesh before reassembling.
In regard to toilet fill valves, it’s better to replace them than clean them. They’re easy to work on and affordable enough that cleaning them often doesn’t make sense.
Adjust the Regulator
It’s fine for a DIYer to adjust their water pressure regulator. These devices usually have an adjustable diaphragm that the user can tweak with a bolt on top of the unit. Turning the bolt clockwise will increase the water pressure while turning it counterclockwise will decrease pressure. If you suspect there is an issue with the regulator, it’s probably best to call a professional.
Fix Leaks
If any of the pipes are leaking, it’s important to fix them right away. Not only do leaking pipes crush water pressure, but they can also cause mold and pest problems. Check appliances, hoses, valves and other fixtures for leaks.
When to Call a Professional
There are times when calling a professional is the best way to increase water pressure. For instance, corroded main valves require shutting the water off at the street, and this is something most municipalities bar homeowners from doing. It’s also a good idea to call a professional or replace a water pressure regulator or water heater, as water heaters can be very dangerous if installed incorrectly.
Also, if all of the above efforts failed, it’s time to call in the pros. Plumbers can locate the cause of low water pressure quickly and usually have all the tools, parts and knowledge to repair it quickly.
