Might try rotating the BFV's and flowmeter 90 degrees, 180 degrees or 270 degrees. Since the disk in the BFV is only partially open @ 1200 gpm, it's orientation relative to the upstream fittings might compound the turbulance coming from those fittings. Just a thought.
You don't mention the applicable edition of NFPA 13. The 2002 edition (that's the olded I have on my desk) and newer would require a K-factor of 11.2 or greater and be listed for storage applications. Reference section 12.1.13.3 in the 2002 edition. The owner may not want to change out...
You might be able to hire a PE to create a new table for you (similar to Table 9.1.1.6.1(a)) based on 10'-6" of pipe. If he/she stamped it and wrote a supporting letter, I'd think you could use it on any future project.
Ed Kramer
Kramer Design, LLC
I don't believe there's anything in 13 to prevent CPVC (or other non-CPVC plastic pipe) from being used as drain pipe. If the applicable edition of NFPA 13 is 2007 or older, the same goes for the supply pipe to the water motor gong. However, a change in the 2010 edition (section 6.9.3.3) now...
You'll find sprinkler protection criteria for idle pallets in NFPA 13 section 12.12 'Protection of Idle Pallets' (20007 version). If you have the handbook (Auto Sprinkler Systems Handbook, not the Fire Protection Handbook), the commentary decribes the serious fire challange that idle pallets...
I found no restriction on gridded dry systems in my '87 edition, but did find it in my '91 edition (section 3-2.3.2). Ask the AHJ when the '91 edition was adopted. I work in some localities that adopt new editions when they're published, others that have a 10 year lag (or more).
Ed K
A 150 gpm pump running @ 150% could easily supply your 177 gpm demand. I know many designers & AHJs prefer to size the pump based on the rated capicity, but NFPA 20 allows usage up to 150%. By your prefered method of tank sizing, this would reduce tank size to 13,500 gallon - closer to the...
FFP1, there is commentary to section 6.1.2 in the 2007 handbook that reads (in part) "Once primed, a centrifugal pump can theoretically operate with a suction lift up to atmospheric pressure. Earlier editions of NFPA 20 allowed centrifugal pumps to operate under suction lift when they were...