Find the Cause of Low Pressure from Hot Water Tap
LESLIE: Free FM WJFK in Virginia is where Muhammad listens to The Money Pit. What can we do for you?
MUHAMMAD: Ah, yeah. I have a question that my hot water when I turn the faucet on and switch it to hot water, that the pressure goes down (inaudible).
LESLIE: Is this only happening at one sink or all the sinks in the house?
MUHAMMAD: All the sinks.
LESLIE: Even in the showers and everything.
MUHAMMAD: Yeah, bathroom, sink; everywhere.
TOM: So whenever you turn the hot water on, you lose pressure.
MUHAMMAD: Yes, sir.
TOM: Well, how old is your house, Muhammad?
MUHAMMAD: My age – 50. (laughing)
TOM: It’s 50?
TOM: Is it … well, I’m thinking if it’s a 50, 60-year-old house, it might have steel pipes. Do you happen to know if you have steel plumbing?
MUHAMMAD: I believe so. Yes.
TOM: Yeah, it sounds like you do because what you’re describing …
LESLIE: Could be a rust buildup.
TOM: Yeah, what you’re describing is consistent with the deterioration process of steel pipes. What happens is the rust forms on the inside of the pipe and it eventually clogs the pipe. The pipe expands and kind of shuts down; it’s almost like a clogged artery, if you can envision that. And the best thing to do if you have steel pipes is, obviously, to replace them.
Now there’s a way to do this where it doesn’t have to be overwhelming. You do it in stages. The first thing that you do is you replace all of the horizontal pipes; the ones that are easiest to get to because they tend to rust first. So that would be the crawl space for the basement. Second to that would be the main water line coming from the street; if that is still steel, that’s a ticking time bomb right there. You want to, definitely, replace that before it bursts at the least opportune time, leaving you guys without any water. And third to that is to replace the pipes that go up through the wall into the bathroom. That’s the most expensive and that’s why we leave that until the end. It’s also less likely to be the main issue.
But if you’re having a water pressure issue and you have steel pipes, it’s invariably going to have something to do with the deterioration of those pipes. And, unfortunately, that’s one of those expensive home improvements that has to be done to all older homes.
MUHAMMAD: The only problem is that it goes … actually goes down only when we turn the hot water on. When the cold water’s there, we don’t have any problem.
TOM: Well, when you turn the hot water on, you’re basically splitting the pressure between the two lines and you’re basically causing more water to have to go through the same pipe. So it could be that maybe one pipe is more deteriorated than the other but, regardless, it sounds to me like the pipes – if they’re steel – they really need to be replaced. Especially since it seems to happen in the entire house.
I mean it’s also possible that you could have a restricted valve somewhere but that’s not likely. It sounds to me it’s more likely that your steel pipes are starting to constrict.
MUHAMMAD: Oh, okay.
TOM: Alright, Muhammad?
MUHAMMAD: Thanks for … thank you very much.
TOM: You’re very welcome. Thanks so much for calling us at 1-888-MONEY-PIT, listening in there on Free FM WJFK.