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Starting Member


Monday, May 23rd 2005, 2:59am

Need help with design ASAP

Hi everyone,

I am starting to design my sprinkler system. The water meter is 5/8", main line size is 3/4" copper. According to this, I can only achieve a maximum of 10GPM. I tapped onto the mainline (in the basement before pressure reducer) to lead to two separate 3/4" PVC line locations (left and right of house). My questions are:
1) If I increase the tapped line size from 3/4" to 1", can I attain the 15 GPM design load? Or am I limited by the 3/4" mainline max 10 GPM?

2) The incoming pressure (main line) is 65 psi. The pressure I get from a hose bib is only 40 psi (after pressure reducer). Since I will tapping from the main line, should I be designing from the 65 psi or the 40 psi?

3) How much pressure do I lose if I increase to 1"? Will the new 1" line have the same 65 PSI?

Thanks for all of your help.

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