a general question regarding water

jonny88

in nyc does anybody know how high water will rise with out a pump.some say 7 stories some say city pumps have been upgraded and water can rise 12 stories.

Bob Gagnon plumbing and heating

Water Question

Do you know what the pressure is?



Thanks, Bob Gagnon

icesailor

Water pressure:

It's the water pressure in PSI Gauge X 2.31' higher than where the gauge is.

100# PSIG = 231' high.

jonny88

city water.

i was meaning more in terms of pressure to run an apartment.a roof tank guy once said to me that the city pumps were upgraded and you can feed an apartment on the 12th floor but a master plumber i know said 7 floors was as high as you can get.i tried google etc,just curious thats all

rlaggren

Where I come from pressure varies

Throughout the city. So depends on where you are, what pressure the city gives you. You test the pressure at any hose connection using a $15 gauge you can get from HD.



From there Icesailer gave you the simple complete answer.



Rufus

icesailor

12 Story Water:

The water gets pumped from the basement by high pressure pumps up to the roof tank. The roof tank then drains water back down to whatever floor, the pressure will be acceptable. If it is a 30 story building, the water may be pumped up in stages. So many floors and a pump. As the water comes back down, Pressure reducing Valves are used to lower the head pressure when the pressure gets too high. This is a gravity system. They may be using bladder tanks and pressure pumps in some cases.

In a normal residence, you can tell the difference in water pressure from one floor to the next floor above. You really can't go much above 75# or you start having faucet failures and water heaters blowing off. It can only go as high as will give you acceptable pressure. From there, you have to pump it higher and use PRV's.

Fire sprinkler systems must be pumped. This was an unmentioned problem with the WTC/9/11. The fire pumps pushing water up to the top floors and the weight of all that water on the structure. If you pump 100 GPM, that's 8330# of water on the floors per minute, or almost 500,000# of water in an hour. At 100 GPM.