Pressure drop after replacing faucet seat

plumbing_noob · 10-23-2010, 12:50 PM

I had a leaking faucet in a guest bathroom (tub/shower) and replaced the washer first; no dice.
I then replaced the seat because I noticed it had a fissure in the side. (to impress upon you my noobness, it took 2 days and 5 trips to the hardware store to even figure out what the seat was and why, after 3 washer replacements, it was still leaking)

Since then the water pressure is pathetic for that tub, everything else is fine so it's not the house in general. I've no idea what the old one was but the replacement is an American Standard #20 7/16" x 24 THD (I've only a marginal idea of what all that means).

It fit physically without issue, and I replaced the cold water side about 9 months ago with the same type (this last one was the hot water side). I guess I can't even be certain the cold water pressure was ok after the replacement since hot water in the tub is primary.

I don't know what information to provide that would be helpful. The people who built the house (custom home) seemed to know what they were doing (at least that's what the inspector said). So far everything I've found is standard sizing.

Thanks.

braindead · 10-24-2010, 06:11 PM

Quote:

Originally Posted by plumbing_noob

I had a leaking faucet in a guest bathroom (tub/shower) and replaced the washer first; no dice.
I then replaced the seat because I noticed it had a fissure in the side. (to impress upon you my noobness, it took 2 days and 5 trips to the hardware store to even figure out what the seat was and why, after 3 washer replacements, it was still leaking)

Since then the water pressure is pathetic for that tub, everything else is fine so it's not the house in general. I've no idea what the old one was but the replacement is an American Standard #20 7/16" x 24 THD (I've only a marginal idea of what all that means).

It fit physically without issue, and I replaced the cold water side about 9 months ago with the same type (this last one was the hot water side). I guess I can't even be certain the cold water pressure was ok after the replacement since hot water in the tub is primary.

I don't know what information to provide that would be helpful. The people who built the house (custom home) seemed to know what they were doing (at least that's what the inspector said). So far everything I've found is standard sizing.

Thanks.

Thing is that a lot of people don't know is that washers and seats are not the same even if they fit, both can cause your problem. The only thing I think you can do is pull the cold seat (IF IT'S WORKING O.K.) and match it EXACTLY and put it in the hot, if you have a flat type washer and the faucet calls for a cone shape that could be a problem also.

plumbing_noob · 10-24-2010, 08:13 PM

I was talking about this with my wife today and she said the cold pressure dropped after the replacement of the seat some 9 months ago, but it just didn't matter as much as the hot, which was working fine.

The original seat (no longer have them) was flat where it hit the washer but the new one, at least the hot, is semi-circled. That may be what is causing the knob turns to be different, from what my wife explained.

I suspect I just have the wrong seats for these faucets and will take the box to Home Depot this week and look for something that matches the threaded side but is flat and has a larger hole.

For my edification, if the seat box says
20
7/16" x 24 THD

Which of these means what? I'm guessing the 7/16" references the inside-pipe thread portion but I've no idea what the 20 or 'x 24 THD' means.

Thanks.

the_man · 10-25-2010, 01:02 AM

the 24 refers to the number of threads per inch. if the seat easily screwed in then it is correct. the 7/16 is the height of the seat i believe. maybe try getting a 3/8" seat and see if its any better since you don't have the original. If you know the brand of the faucet, you might be able to find the oem seats, most brands only used one or two sizes

plumbing_noob · 10-25-2010, 08:03 AM

By "height of the seat" do you mean the diameter of the opening?

Thanks.

the_man · 10-25-2010, 10:14 AM

when i wrote that I didn't, but as i think about it i believe thats what it refers to. i seem to remember looking at seats that were identical in measurements and looked completely different. One thing you can do... take the stem with you next time you go to HD/Lowes. They have a book to match parts for valves. Match the stem, it'll tell you the seat that you need to put in