If you have issues with spitting and sputtering RPZs, it helps greatly if you crack test cock #3 (the one over the zone) to make sure all the air is bled out. This will usually stop most sputtering when there's not a fouled check.
I added an AF loop to an outside porch for a nursing home in Raleigh, and thought I was lucky that the original contractor had installed an RPZ in the hotbox at the curb, so I would only need a drilled check at the loop. Unfortunately, the City plan reviewer didn't agree. He claimed that the RPZ at the curb wouldn't stop cross contamination if someone tapped a domestic service into the yard main between the building and the hotbox. Did I mention that this was off a dedicated 6" fire service? I do not miss dealing with Raleigh at all. On Thu, Jan 21, 2010 at 3:19 PM, Roland Huggins <[email protected]>wrote: > bloody RPZ's have that annoying spitting characteristic too. > > As a sidebar, an RPZ is required for protection against toxic > compounds but even non-toxic chemicals (like propylene glycol) get > pushed into using it. SInce an RPZ is for toxic compounds, a cycle or > two ago I attempted to delete the restriction against ethylene glycol > when an RPZ is used. Needless to say, the TC decided not to depend on > the RPZ that strongly. To be honest, I didn't do an extensive review > to see how stringent the IPC is on compounds that actually are toxic > since I knew it would fly like a lead balloon. > > Anyone that plays with systems with nasty compounds that takes water > from a potable supply, feel free to send me an off-Forum email > educating me further. > > Roland > > On Jan 21, 2010, at 11:41 AM, Matt Grise wrote: > > > Sorry...unclear wording. > > > > I meant that you could use either: > > > > 1) an RPZ at the riser, and a drilled check valve at the loop > > 2) a double check bfp at the riser and an RPZ at the loop > > > > We sometimes use the second setup since RPZ's cost so much more than > > DC BFP's. If the primary riser is 4,6,8" and the antifreeze loop > > only needs a 1.25" RPZ, it can be less expensive to use 2 bfp's. > > > > Matt Grisé PE*, LEED AP > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > > For Technical Assistance, send an email to: [email protected] > > To Unsubscribe, send an email > to:[email protected]<to%[email protected]> > (Put the word unsubscribe in the subject field) > -- Benjamin Young Sprinkler Designer Rowe Sprinkler Systems, Inc. [email protected] _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.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)
