I have adequate water pressure coming into the house, 90psi at the meter, pressure reducing valve lowers it to 60 psi. This is verified by an inline pressure gage.

Some taps have good pressure/flow but the main bath pressure/flow is steadily decreasing slowly. I have replaced shower heads, cleaned filters but no success.

I had a plumber over to assess the situation but he said he didn't know why only some areas are low pressure.

The house is a basement rancher and the problems are on the main level. There is good pressure/flow at other places on the main level. The house is 10 years old. Any ideas why the pressure/flow in one bath is low while one 10 feet away (across a wall) is fine?

Is this loss in both hot and cold or is it in just one? If hot water only do you flush your heater and what's its age? Have you opened up the problem faucets and checked the inlet ports of the cartridges? Lets have more details. Regards, Tom

The pressure loss is both hot and cold. There is a lot of sediment in the faucet filters that has been cleaned and I drained/flushed the hot water heater (gas, approx 11 yrs old). The sediment is no longer showing up on the filters but the pressure is still low. I am investigating the cartridges now to see if they are clogged. When I drained the water tank, I taped a cloth over the end of the hose and got approximately 1/4 cup of white sediment caught in the cloth. Does this help?

Wow. That's a nice amount of sediment. :eek:

When you remove the cartridge(s), be sure to flush out the supply lines: with the cartridge out, hold a bucket over the hole where the cartridge usually is (to contain the splash), and have someone turn the water supply back on full blast for ten seconds. Do this for both the hot and cold water lines. That should hopefully flush out any residual sediment that would normally not come out of the pipe as a result of the cartridge's holes being to small.

To prevent this from happening again, I would strongly recommend installing a whole-house sediment filter on your water main, just after the pressure reducing valve and inline pressure gauge.

Hope this helps,
Moishe
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