Hydraulic question

[cda]

for anti-freeze system, I thought I read before that it can effect the hydraulic calculations??

If so what should I see in the calculations or what should I ask for to be submitted to show it has been fiqured in??

Thanks

 

[RBK]

See NFPA 13 section 22.4.4.5.1. Systems larger than 40 gallons need to have the calcs verified with the Darcy-Weisbach equation in addtion to the usual Hazen-Williams. At low temperatures, antifreeze solutions are more like syrup than water, so the Hazen-Williams underpredicts the friction loss. For smaller systems, the antifreeze solution is pushed out of the system pretty quick, so it isn't much of a factor. Larger systems can take much longer to clear out he antifreeze.

 

[cda]

Thanks.....