Bathroom Guide

Low Water Pressure Inside Home. Outside Water Pressure is Fine. Solution?

Our home was built in 1985 and we have had no problems with water pressure until just recently when we noticed a gradual tappering of water pressure in both of our upstairs bathrooms. The only change that we have made to the plumbing system was a new low-flow toilet and vanity, which required us to shut off all of the water leading to the home. The local water department check the water pressure leading up to the home and the outside faucets are operating at normal pressure. The water meter is also not running at all so we have ruled out any leaks. However, the flow of water pressure continues to worsen with time, such that one of our vanities upstairs not operates at a trickle and we now have noticed the downstairs sinks doing the same. My question is this: Might this be attributed to a Pressure Release Valve (PRV) or might there be another cause? We have PVC piping leading to the home and copper inside, so I don't know if buildup is a problem. Thank you. As an addendum, we had our system inspected by the local water district and they confirmed that we have no leaks in our lines because there is no water flow from the meter when nothing is in use. Its possible that we may have plogged lines, but that doesn't see likely because we removed the screen to the utility sink downstairs and it does not flow well either. When the water district showed up they thought that it might be the Pressure Release Valve, but what confuses me about that scenario is that our water pressure is just fine OUTSIDE the home, but low inside the home. Wouldn't the PRV affect both the outside and inside water pressure?

Public Comments

1. The main shut off vavle to the home isnt used very often so when you shut it to change your fittings you may have relaesed some debris into the lines. I would take off the supply lines in the affected areas and turn the valves on slowly to try and remove any debris. You can also turn off the main again disconnect all supply lines with vavles ope and use compressed air to flush the debris out.P.S. copper will flake over time as well leaving sediment in the lines compressed air will flush this out as well.
2. PRV valve needs looking into. The new stool isn't leaking is it ? The upstairs will sow a low pressure first, just because its upstairs. maybe a leak under the house. Is all supply valves opened all the way ? The copper is less likely to corrode, but the supply valves can corode. Check your piping for leaks. That is all I can think of. the new toilet installed and the problem started? I would do an inspection of the new toilet and related plumbing first.
3. This is gonna be tricky...Since ur water-line coming from street is ok and all u can do is from the shut off valve (lever type or knob type) Lever type in my opinion is better because when it's open u know its open. As for the knob type- after 20 yrs. they get stuck. and u don't know what position the gate is in. This kind of problem requires process of elimination. If the gate problem is eliminated, than the problem is a blockage in the supply line. The trouble shoot now is u have to find where the blockage is. Using compress air or reverse flushing is the best solution to ur problem. Good luck. because u have to cut the supply line to back flush and might require u to go under house or attic to locate where the trouble is. Another thing I like to mention is make sure ur pressure regulator is working before u go thru all that because if some 1 mess with the adjustment, it might limit the flow so much as to cut off the water. (65 lbs.)
4. It is a restriction. The city utility only checks static pressure. That is the pressure when nothing is on. That is all they care about because that is what they are supplying to the home. There are two issues, pressure and flow. If they had checked the pressure with something turned on the pressure would likely drop off real fast anywhere past the restriction. It could be the main shutoff to the house is not open all the way. The one at the meter likely is on or they would have seen it when checking the meter. Often there is another shut off in the house on the main line where it enters the home. That might not be fully open or only barely open which causes it to clog up over time. It is likely in a garage or a basement. It is the one the other posters was saying can go bad and might be broken. But that is rare, possible but less unlikely on a 20 year old home. Or you might have a pressure regulator on the house that is bad. Looks fine with nothing running but when you try to draw water it fails to open up and let enough water in causing the pressure to drop. I think maybe you were talking about a pressure regulator not a Pressure Relief Valve. You know it not a PRV or that would show up like a leak since it is related to pressure only and not the use. If you have a pressure regulator and you are having pressure problems, guess what my guess would be? ;-) Good Luck