The water pressure drop could be due to a clogged aerator at faucet out, a kinked supply line or partially closed shut of that services that fixture.
You actually SHOULD replace the galvanized lines as they completely rust up on the inside. The only other thing that you could do is purge the lines with high pressure air or water. Careful though! You would be taking a risk that a fitting would blow!
Air in the water lines to the upstairs. Not enough water pressure.
New pressure balance faucet or you can install a pressure balance valve in the water lines behind tub or if you have a crawl space you can install it on the water lines there. But install only too the lines to tub faucet. And they are not easy no matter where you install. I would just tell everyone not to use any water till you are done with shower.
THE THING THAT CAUSES YOU TO LOSE PRESSURE AND HOT WATER IS BOTH BATHROOMS ARE CONNECTED TO THE SAME LINES. SO WHEN YOU RUN SOMETHING, THEN RUN SOMETHING ON THE OTHER SIDE, YOU LOOSE POWER THAT YOU WOULD NORMALY HAVE IF ONLY ONE BATHROOM IS ON. THERE IS NO QUICK FIX, TO FIX YOU MUST REPLACE ONE OF THOSE LINES WITH NEW ONES PROBABLY FROM THE BASEMENT. ITS ALOT OF WORK, AND COSTLY. JOE HOJAS
it sounds like there are crossed lines. if there is no water upstairs there has to be a valve that is off. even if there is low pressure it would eventually fill the line and you would get some water.
My first thought is a leaky hot water line.
Voltage is the pressure that pushes electricity through wires (or other conductors) in the same way that water pressure pushes water through pipes.
Think of it this way, if you had a plastic bottle filled with water and you poked a hole in the side, would water squirt out or would air squirt in? If air squirted in, then the air pressure would have to be higher. But since we know that the water would squirt out, we know that the water's pressure must be stronger. Of course, this is under normal conditions. If you pumped the air pressure up enough, then the air pressure may become stronger than standard water pressure. So actually, water pressure is generally stronger than air pressure.
check for leaks
== Answer== I don't think so, but get the air out of lines to make sure.
Davey Pressure Booster Systems with Torrium® control technology would help increase the water pressure from a city water system.
The water pressure in my house is about 140PSI. Which is definitely dangerous. It happens more often than you would think. What happens is a city will use water supply lines which are too small for the water requirements. Therefore, they have to increase the pressure. You wouldn't want a pressure relief valve, because then if the pressure was too high, it would just spray water everywhere to release the pressure. You would want a pressure regulator installed, which is what I am working on for my house right now. Just to let you know though, you may have to get a thermal expansion tank for your water heater if you don't have one. See, the new pressure regulators have a check valve in them, which prevents water from traveling back into the city pipes once it has gotten into your house. When your water heater heats the water, the air bubbles in it expand, which increases the water pressure, and will probably cause your pressure relief valve on your water heater to blow. You can get a cheap water pressure meter at any improvement store to check it out. 50-60 PSI is ok. I would say you could take it up to 70 or 80 PSI safely.