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## system design pressure

OK, i have the blower data from the unit,but it is labeled as follows cooling only units nominal air flow- I/s=1,500 it is also saying that m3/s =1.5
on heat pumps evaporator motor I/s=1,500 and Pa=79-255
can anyone explain these specs how do i find my design pressure using this info oh yes these are Hitachi units
I/s stands for ?
Pa stands for?
m3/s stands for?

2. have your supplier e-mail you the cut sheet for your units. Can you post them for us?

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## system design pressure specs

here you go, sir.

4. Metric.

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m3/s -- cubic meters per second
Pa -- Pascals (pressure) there are 249.1 Pa per inch of water (a.k.a water column, writen as wc")
I/s ?? is that 'l' lower case "L"? (Liter) per second

my math is very rusty ... ?
Pa 79-255 = 0.32-1.02 wc"
1.5 m3/s = 20505 cfm or 2050.5 (5 ton) ?

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## system design pressure

Originally Posted by airprep
OK, i have the blower data from the unit,but it is labeled as follows cooling only units nominal air flow- I/s=1,500 it is also saying that m3/s =1.5
on heat pumps evaporator motor I/s=1,500 and Pa=79-255
can anyone explain these specs how do i find my design pressure using this info oh yes these are Hitachi units
I/s stands for ?
Pa stands for?
m3/s stands for?
what are the proper equations for turning them form metric to american standard, if you do not mind.

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u need 2 instruments to measure air pressure and the velocity, a water manometer for presure and a velometer for velocity inside the ducts.

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I have a new bookmark! thanks beenthere.

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## system design pressure

Digital dutch helped out now i just have to find the toal pressure drops for all of the diffusers coil and filter and then i can find my design pressure, right?

10. The prussure drop of the longest run supply and return. Coil, and filter.
Then you'll have your ASP(available static pressure), and can size your duct drom there.

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