static pressure measurement

[actom]

I need to find proper method to measure static pressure of 100% outside air water cooled air handler. I never did this and I do have a new manometer but don't quite know what I'm doing.

 

[iken]

Measure the pressure at the supply side (SP Outlet)of air handler, and at the return side of the air handler (TP Inlet).

The supply should yeild a positive value, and the return a negative value.

The tatal static pressure of the air handler will SP Outlet - (minus) the TP Inlet.

i.e Pressure SP Outlet 69 Pa
Pressure TP Inlet -272 Pa

Unit Static Pressure = 341 Pa

This can also be done at the fan to give the fan static pressure

 

[lilliput1]

Your manometer may not have enough range. Verify before you connect it because you can blow out the fluid. The fluid bottom should be connected to the high pressure side. The fluid top to the low pressure side. The height difference between the fluid would be calibrated in inches water gauge pressure difference. If you want you can have one port be at the ambient athmospheric pressure so the DP reading would be pressure above (or below) ambient atmosphere.

 

[lilliput1]

Your manometer may not have enough range. Verify before you connect it because you can blow out the fluid. The fluid bottom should be connected to the high pressure side. The fluid top to the low pressure side. The height difference between the fluid would be calibrated in inches water gauge pressure difference. If you want you can have one port be at the ambient athmospheric pressure so the DP reading would be pressure above (or below) ambient atmosphere.

 

[lilliput1]

Oh don't forget, the manometer must be level for accurate reading.

 

[MintJulep]

The Dwyer Instruments catalog used to have a very nice section detailing how to take pressure and air velocity measurements.

They don't seem to have the same level of detail online, however this may help a bit.

https://www.dwyer-inst.com/htdocs/primer.html