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How to solve low water pressure problems.

Living with low water pressure in your home can be a real annoyance, you canít take a shower if someone else is doing the dishes, or washing clothes, or you have to keep the cold water in the shower, to the almost off position because the hot water pressure is so low, some of the causes are simple to fix and others are more involved.

This is a guide to help you understand why you are having low water pressure problems.

I will cover the many things that cause low water pressure, and the different low water pressure problems, like is it the whole house that has low pressure?, or just the hot water side that has low water pressure?, or just part of the house? Or just a single faucet or shower that has low water pressure?

I will be addressing the causes of all low water pressure problems you may have in the following pages.

Please click on the link that best describes the problem you are having.

My whole house has low water pressure.

There are a number of reasons that will cause your whole house to have low water pressure.

If you have a pressure reducing valve "PRV" required by your town or city water system, the PRV may be defective and needs to be replaced.

If you have a main line sediment water filter, it may be time to replace the cartridge.

In some areas, the water pressure simply sucks, check with your neighbors to see if they are having the same problems, if so you need to call the town or city.

Old galvanized pipes, over time old galvanized pipes will rust closed from the inside of the pipe, the outside of the pipe may look fine, but the inside may be clogged up, the fix is a re pipe of some or all of the galvanized pipe.

In some instances the problem is at a point where the galvanized pipe is screwed into a brass fitting, like a valve, the dissimilar metals cause the galvanized pipe to rust much faster, so it may be possible to simple replace that section of pipe, if you do be sure to use dielectric fittings between the galvanized pipe and the brass or copper.

A main valve failure, sometimes when you turn a valve off, it will not turn back on, sometimes it will stay off completely and sometimes it will open part of the way and stop.

If the valve handle continues turn and never reaches a stopping point, chances are the gate stem broke, and the gate is stuck either partly open or closed.

On a soft seat valve, the rubber washer can break off and get clogged inside the pipe.

If you have low water pressure in your whole house but none of the above reasons fit your problem, please use the 24/7 Help Line for more help and information.

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Low water pressure in part of the house.

This article is about a section of the house having low water pressure, if you are looking for information on low pressure to the hot water only please go to this link.

If you are looking for a single sink or shower problem go back to the top and use a different link.

So what are the causes of low water pressure to part of a house or a single bathroom?

Some homes have isolation valves, isolation valves allow you to turn the water to a section of the house off, it is possible that one of the valves going to the section of the house with the problem is defective, clogged or the gate is broken.

A leak below the slab, some homes have pipes that run under the cement slab from one part of the house to the other, if the underground pipe springs a leak, it will cause you to have low water pressure to that section of the house.

Sometimes a partial pipe repair will leave some old galvanized pipe in the home, if that part of the house has old galvanized pipes, they may be clogged.

A kinked line, sometimes soft copper or plastic tubing will kink restriction the flow of water.

If I did not cover the problem you are having in this article, please use the 24/7 Help Line, for more help and information.

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Low water pressure on the hot water side only.

This article is about having low water pressure on the hot water side of all of the plumbing is the house, if you are having a problem with just a single faucet or a section of the house and only have 1 water heater, please see other links at the top of this page.

The most common cause of low pressure on the hot side, is related to the water heating system.

Some homes have a boiler or furnace that has a hot water coil in it, this coil needs to have a flow restrictor installed on it, so that the water will not flow through it so fast, that it can not heat the water, so a little drop in pressure is normal, but this coil is subject to clogging due to hard water, so the problem may be the coil is closing up, this can be cleaned by a professional, with a special acid made to burn the lime buildup out of the coil.

Some on demand water heaters have the same problem the coil has, the flow restrictor and the unit clogging.

A valve connected to the inlet of a water heater may be partly closed or broken, a washer from the inlet valve may have broken off and is stuck in the water lines to the water heater.

A copper or brass connection to the water heater without a dielectric union or fitting, may cause the line where the dissimilar metals touch each other to rust out on the inside of the pipe.

And a rare situation when a glass marble, that is part of the water heaters back flow prevention system, breaks out and gets stuck someplace down the hot water pipe.

If you have a unique problem that I did not cover in this article please use the
24/7 Help Line for further assistance.

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I have low water pressure in the shower only.

If you have low water pressure in the shower only, it is likely a clogged water restrictor in the shower head, to fix it remove the shower head and clean out the water flow restrictor in the shower head.

Sometimes it can be a clog in the pipe going to the shower head and sometimes a washer will break apart and get stuck in the shower valve, this can be a real pain to clean out.

If your problem is not as simple as a clog in the shower head, please use,

The 24/7 Help Line for detailed assistance.

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Only 1 sink has low water pressure.

Most of the time if you have just the sink with a low water pressure problem, it is caused by dirt in the aerator, the screen at the tip of the faucet spout.

For full instructions on how to clean or replace an areator on any faucet, please see this page.

Other things that will cause a single sink to have low water pressure are, the flexible tubing under the sink is kinked.

The valves are not open all the way.

Some thing is stuck inside of the faucet.

If your problem does not fit the above statements, or you need help with any of them, use the 24/7 Help Line.

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The toilet takes forever to fill after it has been flushed.

This is a very annoying problem, you flush the toilet and you have to wait 15 minutes for the tank to refill.

Many times it is caused by dirt in the toilet fill valve otherwise know as the ballcock.

Sometimes you can simply clean it out and it works normal again, but sometimes it is just as easy to just replace the toilet fill valve.

Please see this page to replace the toilet fill valve.

Sometimes the flexible water supply line to the toilet gets kinked.

Sometimes the rubber washer inside the toilet stop or shutoff valve will break off and get stuck in the supply line.

If you need help figuring out why your toilet takes forever to re fill, use the
24/7 Help Line

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Other reasons you may have Low water pressure problems.

You may have good pressure on both the hot and cold sides of the faucets, but when you use more than one faucet at a time the pressure drops in both faucets.

There are a few things that cause this problem, one is you may have a whole house sediment filter that is not so clogged, that it the pressure to drop when only one faucet is being used, but restricts the volume of water needed for more than one faucet, the simple fix replace the cartridge,

Again with the galvanized water lines, they may be just clogged enough to reduce the needed water volume to supply all the faucets.

Under sized water pipes, I see this too many times, some want to be plumber will run all of the water lines in the house on a single 1/2" water line.

A single 1/2" water line, copper, brass, plastic or other, simply can not deliver the required water volume needed to supply all the fixtures in a home.

Some think that having real good water pressure will make it better, but only X amount of water can pass through a 1/2" water line.

The rule of thumb with water line sizing is, for a home with up to 1 and a half bathrooms you need a 3/4" line and each 1/2" line must come off of the 3/4" line.

To be sure it is sized right, there should not be any 1/2" tees in the system.

Only 3/4" by 1/2" tees should be used and at the end of the line a 3/4" by 1/2" by 1/2" tee should be used.

A 3/4" line goes to the water heater and comes out of the water with 3/4" pipe and the same as the cold, NO 1/2" Tees.

If you need help with this or have a question that was not covered, use the
24/7 Help Line.

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The water pressure in your house is high sometimes, then drops to nothing.

This is a well pressure switch problem.

What is happening is the pressure switch is not registering the pressure in the pipes.

Sometimes the switch is bad and the springs are worn out and it will not click on or off when it is needed.

But sometimes the pressure switch is fine and the water line going to the pressure switch is clogged or partly clogged.

Remember that a pressure switch has electric power and it is connected to a water line, this is a bad combination.

I have found that the fitting attached to a pump is clogged at the pump. I have also found that the clog can be in the bottom of the pressure switch where the nipple attaches to it.

The bottom line is the pressure switch needs to be removed, cleaned or replaced, and any lines tied to the pressure switch need to be cleared.

If you need help with this, use the

24/7 Help Line

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The water in my house pulsates.

This is a serious problem, if your water pulsates when the faucet is on or when the toilet tank is filling back up, your well tank is water logged.

A well tank being water logged means it has no air in the top of it, with no air the water can not be compressed, so the pump keeps coming on and off, if you go to where the pressure switch is you will hear it clicking on and off over and over again whenever the water is running.

A well pump short cycling like that will burn out the pump, in a short amount of time.

You need to either replace the well tank, or get air in the top of it.

If it is a bladder type tank, any air you put in will only last for a short time.

You need a new well tank.

If you need help with this, use the

24/7 Help Line

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