Travis, This doesnt address your question, but I'm curious if the entire AF system is subject to outdoor temps (or just part of it).
I ask, because if a significant part of the system is in a heated area, then it further complicates selecting an appropriate viscosity. My limited understanding of HydraCalc is that a single viscosity and a single density is entered for the entire calc (if I'm wrong, someone please correct me). Do you use the high viscosity (extreme min temp), the medium viscosity (average min temp) or the low viscosity (room temp)? Obviously the room temp viscosity wouldn't be appropriate, but how's a designer to choose? As in your example, the selected viscosity can make a whale of a difference in system costs. I've yet to calc an AF system using Darcy-Weisbach, so I'm hoping someone can enlighten me. Ed Kramer Littleton, CO > Ok..another viscosity question. > > When using HydraCalc to calculate antifreeze systems using the Darcy > method, it asks for viscosities of solutions. I have a data sheet with > the viscosities at various concentrations and various temperatures. My > question is, do you use the average daily minimum temperature for an > area, or the extreme daily minimum for an area? For this particular > project, the difference is 40°F in the 2 temperatures. With the average > daily minimum temperature, the system works with the available pressure. > With the extreme daily minimum, the city supply is not even close. > There is a 100+ psi swing in the demands. > > So, do we go with average minimums, or extreme minimums? > > There is always the option to go to a dry system, but the increased > design areas and reduced c factor will also force a pump on this > project. An anti-freeze system at average daily minimum works without a > fire pump. > However, we don't want to design/install an inadequate system. > > > Please feel free to call if you have any questions or comments. > > Travis Mack, SET > MFP Design, LLC > 2508 E Lodgepole Dr > Gilbert, AZ 85298 > 480-505-9271 > [EMAIL PROTECTED] > _______________________________________________ Sprinklerforum mailing list http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [EMAIL PROTECTED] To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)
