assume, practical...are those definitions in the 2007 edition? I can't find them in 2002.
I included the reference only to show the importance the manufacturer places on removal of air from the system. I assume it is not only the water hammer issue but the real possibility of distortion or failure(burn-through). (A.6.3.6 NFPA 13 2002 ed.) I have found nothing quite as disconcerting as walking through a jobsite on a monday morning to find heads, escutcheons and burned off head adaptors littering the floor. Lightning struck roof, system 2 weeks from hydro. ----- Original Message ----- From: "Ron Greenman" <[email protected]> To: <[email protected]> Sent: Saturday, May 16, 2009 8:26 PM Subject: Re: CPVC w/o water between riser and FDC Thomas, When applying water to the FDC we can assume we are doing so to a pipe that has already been tested for integrity and not worrying about dry fits, unconnected pieces, etc. as we would in a new system (property damage), nor full of air as we experience in a new system (potential explosive decompression and the resultant bodily injury). We can also assume that we are adding water to supplement a flow that is already occurring and therefore there are "holes" (discharging heads) already in the pipe. Unless we unleash the damned hellish hounds of hundreds of pounds of over-pressurization upon the system I doubt that we will even have the mildest of water hammer. And as a side note we have hooked this FDC up to the truck because the building is on fire and already experiencing property damage. Now should the pipe run from the FDC be as short as possible? Certainly the dry portion, and we can limit an FDC dry run of 100 feet (or more, or less) by placing the FDC check valve as close as practical to the FDC itself. But if placing it at the riser is the most practical location (my ridiculous 100 foot run excepted) then so be it. I wonder how much pressure I would have to apply to a CPVC system with only one head flowing before I've created a situation that would rupture piping and connections already tested to 200 psi in a static state? I'd bet more than my fire engine could generate. On Sat, May 16, 2009 at 4:38 PM, Thomas Watt <[email protected]> wrote: > IMHO, no. > > The FDC check should be installed as close as possible to the FDC to > eliminate the dry run. > > >From the Harvel install guide: > "When pressure testing, the sprinkler system shall be slowly filled > > with water and the air bled from the highest and farthest sprinkler > > heads before pressure testing is applied. Air must be removed from > > piping systems (plastic or metal) to prevent it from being locked in > > the system when pressure is applied. Entrapped air can generate > > excessive surge pressures that can result in bodily injury and/or > > property damage, regardless of the piping materials used." > > > > ----- Original Message ----- > From: "R Richardson" <[email protected]> > To: <[email protected]> > Sent: Friday, May 15, 2009 1:04 PM > Subject: CPVC w/o water between riser and FDC > > >> We are reviewing a proposal for a wet pipe sprinkler system using CPVC >> pipe. However, there is a run of CPVC pipe between the FDC and the riser >> that is dry, is this standard practice or acceptable? >> >> Thanks, >> >> Rich Richardson >> Seattle Fire Department >> >> _______________________________________________ >> 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) > > > -------------------------------------------------------------------------------- > > > > Internal Virus Database is out of date. > Checked by AVG - http://www.avg.com > Version: 8.0.233 / Virus Database: 270.10.16/1930 - Release Date: 2/2/2009 > 7:51 AM > > _______________________________________________ > 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) > -- Ron Greenman at home.... _______________________________________________ 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) -------------------------------------------------------------------------------- Internal Virus Database is out of date. Checked by AVG - http://www.avg.com Version: 8.0.233 / Virus Database: 270.10.16/1930 - Release Date: 2/2/2009 7:51 AM _______________________________________________ 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)
