Doesn't the main have to be pitched? 8.15.2.3.1 Dry Pipe Systems in Non-Refrigerated Areas. In dry pipe systems branch lines shall be pitched at least 1⁄2 in. per 10 ft (4 mm/m) and mains shall be pitched at least 1⁄4 in. per 10 ft (2 mm/m).
I think the contractor was confused between preaction and dry systems. It used to be that a preaction system in a heated area did not have to be pitched. However, as long as I can remember, dry systems have been pitched. On 3/14/2010 1:57 PM, Jay Jay Blocker wrote: > I have a scenario I would like some input on. We have a property with five > buildings all five buildings are five stories tall with dry systems in the > attics. 4 inch schedule 10 main with Tyco attic heads on 1.25 inch sprigs. > 4 of the buildings have all the main and sprigs in the attic with only the > supply and the drum drips in the heated floor below. Building five has the 4 > inch main hung in the hall way below with 10 foot sprigs penetrating the > rated ceiling into the attic. NO pitch on any of the main. I have not seen > a dry system done this way before but can not seem to find anything that says > it cant be done this way. (13-2002) Any input on this arrangement? > > The issue I am having is the 4 inch pipe is developing pinhole leaks at only > 18 months of service. Upon replacement of a section of pipe a sludge about 1 > inch thick was discovered as well as large amounts of water. I know the > pitching will correct the draining of the water but our concern was where the > water was coming from. The installing contractor told the customer "Idid you > a favor to keep your main from freezing." The question was asked if it was > possible that all the sprigs being in the cold area and the main in the dry > could be the cause for the excess water (condensation). Also is there any > place I can send a sample of the sludge to get it tested for possibility of > MIC? > > Thanks for the help. > > Jeremy Blocker > EFPS > (303) 353-9712 > > > > _______________________________________________ > 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) > _______________________________________________ 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)
