A fast drop in only one faucet means there's a problem with the faucet. Rapid low pressure affecting one area of the house may mean a corroded pipe issue. An abrupt water pressure drop affecting the whole house may mean a water main break (municipal water) or a well pump problem (well water).
Check to make sure the valve is completely open. If the shut-off valve isn't to blame, sediment buildup is the next probable cause. Mineral and sediment buildup within the tank can cause low water pressure.
Low water pressure can occur when the aerator (which reduces the volume of water coming from your faucet without changing pressure) has mineral or rust buildup. The fix: Remove the aerator to see if it needs cleaning. Give it a good scrub and then replace it to determine if it was the cause of your problem.
It may be caused by debris such as dirt, sand, solidified oil and grease, food particles, or foreign objects. Pollutants can block pipes if they back up due to fractures in the water main. Mineral buildup clogs pipes over time and causes the water pressure to go down, as there's less space for water to travel through.
Check for a pressure-reducing valve (PRV) mounted on your water main. Most come set from the factory for 50 psi, but you can adjust them up or down by turning a screw on top. PRVs can also go bad after 10 to 20 years. So if yours is old, it might be time to replace it.
If there's an accumulation of sediments in your hot water tank, it can lower your water pressure. The presence of kinks in the flexible water pipes used in water heaters can result in low water pressure. If the shut-off valve isn't fully open, water pressure can drop.
Clogged Pipes Can Impact Water Pressure
The issue could run deeper, resulting in more serious plumbing headaches. Clogged pipes are one of the most frequent causes of low water pressure.
Check Your Aerator
If you have especially hard water, aerators become clogged with hard water buildup, a common cause of low water pressure in kitchen fixtures. Clean your aerator for a quick and easy DIY fix. Remove the aerator from the faucet using pliers and a towel (to prevent scratching).
The city could be flushing hydrants.
In any of these cases, the pressure loss will be temporary. But when the water does come back online, it will definitely kick up sediment, which can clog supply valves and faucet aerators. Be prepared to flush them if the pressure seems low when the water comes back on.
These air bubbles usually find their way to the highest points in your plumbing system, lower water pressure, and inhibit the flow of water through the pipes. Air in the water piping system can cause rust and corrosion. Rusted pipes weaken, and the rust can drop sediment into your water.
Some of the first signs of a failing pressure regulator are a leaking water heater or commode. The water coming from a faucet may also exit with such force that splashing or water “hammering” may occur.
Water pressure regulator replacement: $250 to $1,000. Pipe section replacement: $500 to $4,000.
How long will a Water Pressure Reducing Valve last? The life expectancy of a water pressure regulator is most commonly in the range of 10 to 15 years. However, you may see a regulator malfunction at three years and one still properly functioning at 20 years old if regularly maintained.
In addition to the mains stop valve outside the home, you'll have one inside. Your internal stop valve is most likely beneath the kitchen sink. Your external stop valve is owned by the water company. If it's open yet the pressure here falls below one bar, it's their responsibility to improve it.
A quick and easy way to increase water pressure is to adjust the pressure-reducing valve, which can be found in your home, usually close to your water meter. If your pressure gauge reading was low, make slight adjustments to your regulator.
Low water pressure can damage washing machines over time. The problem becomes worse the more clothes are being washed at one time. If the water pressure is low, the machine has to work harder to get the water through the hoses and into the washer.
However, when low water pressure originates from an issue specific to your home, such as a water pipe or your pressure regulator fails, plumbing repairs can correct the problem.
Find the spigot closest to your source of water. Make sure all the taps and other water uses are turned off in your house. Now turn on the spigot and see how long it takes to fill the bucket. Dividing the number 60 by the time to fill the bucket will give you the gallons per minute number.
To return to full pressure only takes seconds. Flushing and recirculating takes minutes if you open all the taps, with the exception of tank water heaters.
It's important to contact a local, reliable plumber who will be on hand to unblock your drain again if it becomes a recurring issue and help you understand why the problem might keep happening.