Circuit pressure

[dianad]

Hi,

I'm facing the following problem: in the project, i've calculated the pressure drop along a closed circuit. The calculations gave me aprox. 3,5 mH2O of pressure drop. This was calculated for a optimal flow of 240 lt/h. After the installation was made, the max flow that the pump was able to provide was 120 lt/h. The first thing that i thought was that the circuit pressure loss was much greater than th one i've calculated in the project and therfor the pump was working in a lour point of the pump curve, so that it could overcome that loss.

After this i've started to think much deeper in this, and i've figured another reason, that i would like to see commented. In this circuit, the pressure vessel is installed after the pump. I wonder if the pressure is limited by the expansion vessel defined pressure, wich may not be enough to overcome the circuit pressure loss.

I would like to hear some comments about this.

Thanks!!

 

[Artisi]

Air could be a problem - seems that you need an air valve of some description at the high point, at least this eliminates one potential problem.

 

[btrueblood]

"Manometro" is Spanish for pressure gage, I think. There's one on the pump outlet, and one on the downstream side of the...air exchanger? Ought to be one on the pump suction, but hey. Dianad, can you tell us what the readings from the various pressure gages is?

 

[BigInch]

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