Water pressure

[Twowaxhack]

If I have a toilet on the 8th floor that requires 40 psi to operate and the distance between each floor is 10’

What minimum starting pressure would I need to operate the toilet

A) 65 psi
B) 73 psi
C) 80 psi

Please explain how you arrive at your answer.

 

[GReynolds929]

C) UPC 610.8 - 0.5 per ft psi elevation loss 80’x0.5psi=40psi+40psi=80psi
Possibly could have been B, but math doesn’t add up. B) UPC A104.2 - 0.43 psi per ft elevation friction loss 80’x0.43psi=34.4psi+40psi=74.4psi

 

[Twowaxhack]

Thanks for answering Greynolds.

No one else ?

 

[Geofd]

For every 2.31 ft you lose 1lb of pressure

 

[Twowaxhack]

For every 2.31 ft you lose 1lb of pressure

What’s your answer ? How did you arrive at that answer ?

 

[Geofd]

I remember those numbers from the plumbing formula's we use, but I had to look ok it up

For every 2.31 ft you lose 1lb of pressure

I had to look it up, I haven't used these formulas in along time just know some numbers stick in my mind

 

[Twowaxhack]

I remember those numbers from the plumbing formula's we use, but I had to look ok it up

I had to look it up, I haven't used these formulas in along time just know some numbers stick in my mind

Is your answer A,B or C ? And please post the math of how you arrived at your answer.

thanks !!!

 

[Helper Dave]

In WI, we use .434 for friction loss in elevations, so, like GReynolds said ... .434 x 80= 34.72 + 40 = 74.72, and you don't ever round down for pressure, so 80.

 

[Twowaxhack]

Helper Dave’s answer is
C) 80 psi.

And he showed his math.

Thank you

 

[Twowaxhack]

Bump

 

[Twowaxhack]

I say the minimum starting pressure would be C) 80 psi

I agree