Pressure, No Pressure?

We need some input, or confirmation of a problem in the house. When we first turn on the water at any location in the house, the water comes flying out like we would expect it to. Our area seems to have a lot of water pressure and never had any issues with it. However, we do now. After about 3 seconds, the flow is minimal, Forget about taking a shower, there isn't any pressure. Its the same for hot and cold water. Turn it off, and 3 seconds later its blasing for 3 seconds, then back to slow flow. I'm suspecting that its at the inlet side of the house, located in the basement. Its all copper after galvi pipe, and who knows the age. Anyine want to take a stab at this?

Those symptoms point to a defective pressure regulator, located usually at the point the water main enters the house.

Could it really be that easy? I was counting on worst case scenario with plugged pipes. The house is 80 years old, but the plumbing isn't nearly that old.

PRV, but if the galvanized supply lines are all corroded, it could be the size of a pencil inside. Might need to replace it back to the city line.

I've seen this happen when a rock or other debris gets in the main, and it only plugs when there is flow. does this happen at the outside hosebibs? If you are on a well it could be a problem with the pressure tank.

JetBote said:

We need some input, or confirmation of a problem in the house. When we first turn on the water at any location in the house, the water comes flying out like we would expect it to. Our area seems to have a lot of water pressure and never had any issues with it. However, we do now. After about 3 seconds, the flow is minimal, Forget about taking a shower, there isn't any pressure. Its the same for hot and cold water. Turn it off, and 3 seconds later its blasing for 3 seconds, then back to slow flow. I'm suspecting that its at the inlet side of the house, located in the basement. Its all copper after galvi pipe, and who knows the age. Anyine want to take a stab at this?

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I suspect the galvanized lines. (or a very slim chance of a clog or pinch) Lots of homes have "New Plumbing" that connects to the original 3/4" galvanized supply line from the water main at the street. This pipe rusts or fills with gunk on the inside, creating an ever smaller pipe until you start to notice the problems. What this means, is you have a flow problem, not a pressure problem. Not enough water can come through that small feed to make your larger in home plumbing work right.



You can test this with a few things. If you have a pressure / flow guage, you can get the Gallons per minute coming out of a hose bib closest to the main water line.

If you are on good terms with a neighbor, ask to connect a hose from their house to yours. You will need a Double Female hose adapter. Open both hose bibs, you are using his supply line to charge your interior plumbing. Try shutting off your main supply. See if it effects the Pressure / flow rate.

Expensive but best solution if supply line is rusted, is going to involve lots of digging. I have seen people who get by on the short term with adding a pressure tank in the basement to act as sort of a water storage reservoir. Using the reduced flow to slowly refill the tank after you turn off the sink etc.

Or you could just move.