Coaxial Exchanger PSI drop?

I've seen some of the recommendations for pump sizing on this forum, None seem to include the PSI/ ft hd drop in the heat exchanger.

I'm wondering why? This is part of the system, and water has to flow through it also.

I cant find a listing for Climate master, or Bosch w2w units psi drop in the coaxial exchanger.
With the help of Google I found a 3ton coaxial exchanger that lists 4.4 PSI drop at 9 gpm or a little over 10 ft hd. This would make a big difference in the actual GPM flow if you did not figure this in.

Are all coaxial exchangers the same? is it safe to assume a 3ton w2w GSHP has a 4.4 psi drop at 9 gpm?

Thanks

 

They are all very close. I will see if I can get you real numbers.

 

Andy, it's in the document for the unit (in the performance charts)... The way the actual flow is measured on a unit is by taking the In/Out PSI and then looking up the gpm on the unit's chart. So given a unit, you know your target gpm, so you can see what the PSI delta should be.

Looking at a older CM doc, 3 ton unit... EWT at 30 degrees; 9 GPM == 5.7 PSI or 13.1 ft