Pressure drop required for viessmann 100 main heat exchanger

[Sharp Point]

As title guys n gals, just doing some pump calculations and i cant find the pressure loss of said heat ex. Is it written as metre head or pascals?

thanks peeps

 

[doitmyself]

Is it the Open Vent version?

 

[Sharp Point]

Is it the Open Vent version?

indeed it is.

 

[doitmyself]

Your best option is to ask Viessmann.

As for metre head or Pascals (surely kPa?), it can be either, or even in millibars! In any case, the resistance is not a fixed value but varies with the flow rate through the hex. However Viessmann should be able to provide you with a graph showing this info.

 

[Stanios]

If its hydraulic resistance in question I think it only affects flow rate rather than the pressure

 

[doitmyself]

If its hydraulic resistance in question I think it only affects flow rate rather than the pressure

Hydraulic resistance and pressure drop are the same thing. It varies with the flow rate through the hex. Look at the graphs in, e.g., any Vaillant Ecotec boiler installation manual.