head loss

martin

Trying to figure head loss so I can size a circ, hoping someone can check my figures. My Wirsbo radiant summary says Ihave a maximum of 3' of head loss, this does not include supply or return piping. My main header piping is 10' of 1.25 cu. and the run to the largest manifold is about 20' of 1"cu. My flow thru the header should be about 14 gpm with all zones calling, my chart says that should be about 1.3' of loss for header S&R. Manifold feedpipe shold have flowrate of 4.8 gpm so that should be around 2' of loss. The Wirsbo loss was figured at 20 degree loss and the other was at 10 degree loss, how much will that change the loss on the main manifold. manifold is 9 loops of 240 x1/2 hepex

Mark Eatherton

Doubling flow

increases head by around 3.3 times. Reducing the flow rate by half reduces head by .3

14 GPM through 1" exceeds recommended velocity. (Good for up to 8 GPM and still maintain reasonable velocity)

These numbers are found in Siggies book.

ME