Loss of Pressure (Whole House)

I need help! I live in a 5 year old home in California. I am on city water. 2 weeks ago I started to loose pressure in the master bath/shower. Didn't get to it and now as of three days ago all water pressure is low (both hot and cold). Please help I need a shower (not a dribble, and I have laundry and dishes to do

pressure control valve

There should be a valve with a hex head bolt sticking out of it on the main water supply line coming into your house (probably next to the lawn sprinkler control valves in your front or side yard). That valve controls the pressure coming into the house so that your pipes don't burst. Usually they fail by going to full pressure, but maybe yours is different.

Try turning the hex bolt in a few turns. If that doesn't work, a replcement can be found at almost any hardware store ($30.00). Bring the old one with you for reference.

First thing, are your neighbors having similar problems?

Do you have galvanized pipes either coming to the house or in the house? Probably not if it is 5 years old.

Is the shutoff valve fully opened?

Is there a pressure reduction valve?

Do you have a filter on the incoming line?

Do you have a water softener?

You can buy an inexpensive water pressure guage that you can hook up to your washing machine supply or an outside hose faucet, or with adapters, to another faucet after removing the areator. Check it out. There is a difference between pressure and volume. Your pressure may be fine, but if there is a restriction, you won't get enough flow. If the pressure is very low, you won't get much flow either.

What Jim is getting at is a common misunderstanding many people have. Water flow and water pressure, although related, are not the same. If your water line is restricted somehow, you could have normal pressure when checked with a pressure gauge, but have very limited flow. Check the areas suggested, the problem has to be between the main supply line (meter) and the first point of use, so you just have to eliminate each possibility until you find the problem.