I had a plumber replace an upstairs bathroom faucet yesterday (embarrassing to admit here, but he was here for other, more complicated work). Now I have virtually no water pressure up there. The same thing happened when we replaced a faucet downstairs. My house is over 100 years old. Do new faucets have some water saving device that could cause this? Could replacing the faucet be enough to knock loose sediment around in the pipes so that the pipes become blocked? I will, of course, have the plumber come back, but his main selling point is that he is always available, not that he is good.