To answer your question Todd, The SYSTEM is required to be vented each time the system is drained and refilled. The check valve or physics do not come into play.
The 2-story example you provided is only one System. Therefore, if drained, then refilled, it would be the entirety of the System. Separate Control valves and a drain indicate that only that system would be drained then refilled. It is about corrosion and not drifting air bubbles. Now, to Taylor’s point about CPVC, what if following the control valve, there is 1 foot of SCH10 pipe, then a transition. Accordig to the book, steel piping is present. So, a vent is required. R/ Matt A.16.7<https://link.nfpa.org/publications/13/2022/chapters/16#ID000130006575> A manual or automatic air venting valve can be a reasonable approach on wet pipe sprinkler systems to reduce corrosion activity. The purpose of the air venting valve is to exhaust as much trapped air as possible from a single location every time the system is filled. The objective of venting is to reduce the amount of oxygen trapped in the system that will fuel corrosion and microbial activity. It is neither the intent nor practical to exhaust all trapped air from a single location on a wet pipe sprinkler system; however, more than one vent can be used on a system at the designer's discretion. Interconnection of branch line piping for venting purposes is not necessary. An inspector's test valve can serve this purpose. The air venting valve should be located where it will be most effective. System piping layout will guide the designer in choosing an effective location for venting. In order to effectively accomplish venting, it is necessary to choose a location where the greatest volume of trapped air is vented during the first fill and each subsequent drain and fill event. The vent connection to the system should be located off the top of horizontal piping at a high point in the system; however, the vent connection can also be effectively located off the side of a riser or riser nipple at a high point in the system. Manual air venting valves should be accessible. The manual air venting valve should be located at an accessible point and preferably not over 7 ft (2.1 m) above the floor. Automatic air valves are not required to comply with the accessibility requirement of manual air venting valves; however, it is recommended the designer locate automatic air vents over areas without ceilings, above a lay-in ceiling, or above an access panel. Each wet pipe sprinkler system should be vented every time the system is filled. Please rate our customer service<https://survey.medallia.com/?emailsignature&fc=3539&bg=Fire%20and%20Fabrication> Matthew J. Willis, CWBSP, CET Engineering Manager – Southwest Region FERGUSON FIRE DESIGN, LLC A Wholly Owned Subsidiary of Ferguson Fire & Fabrication, LLC 3508 Hwy. 557 West Monroe, LA. 71292 C: 307-236-8249 matthew.will...@ferguson.com<mailto:matthew.will...@ferguson.com> www.FergusonFire.com<http://www.fergusonfire.com/> From: Ken Wagoner <k...@parsleyconsulting.com> Sent: Monday, October 9, 2023 7:26 PM To: sprinklerforum@lists.firesprinkler.org Subject: [Sprinklerforum] Re: Air venting I understand and agree Todd, before I shot my mouth of to the layout tech I wanted to make sure I was headed in the right direction. Thank you! Ken Wagoner, SET Parsley Consulting 500 West Mechanic Street Harrisonville, Missouri 64701-2235 Phone: (760) 745-6181 Visit the website<https://linkprotect.cudasvc.com/url?a=http%3a%2f%2fwww.parsleyconsulting.com%2f&c=E,1,Y5zKJKPEh1mBEBqSR-VE9cUKl5y-eyP8BpvmE_5j9ZqW2eJbNphYzrCMBZ-2YuX6d-RRkHI4gQ1FV-cvOeCfRC58uZS9NiToZv2mx7909oCqLvCW_n5hDHeK&typo=1> On 10/9/2023 11:27 AM, Fpdcdesign wrote: Ken, I think you would have to with the check valve. I would push back a little in that by adding a normally open valve and a flow switch or manifold would not change the physics of the system enough to warrant the additional vents. If you had a 2 story building without zone valves, you would only need one vent. However, if you add normally open valves and flow switches, you would now need 2 (or 3?). From the standpoint of physics, why? Todd G Williams, PE Fire Protection Design/Consulting Stonington, CT 860-535-2080<tel:860-535-2080> (ofc) 860-554-7054<tel:860-554-7054> (fax) 860-608-4559<tel:860-608-4559> (cell) On Oct 9, 2023 at 12:06 PM, <Ken Wagoner<mailto:k...@parsleyconsulting.com>> wrote: Yes, Todd, on each floor, as they're using a Victaulic UMC manifold which includes a check valve. thanks for the information, Ken Wagoner, SET Parsley Consulting 500 West Mechanic Street Harrisonville, Missouri 64701-2235 Phone: (760) 745-6181 Visit the website<https://linkprotect.cudasvc.com/url?a=http%3a%2f%2fwww.parsleyconsulting.com%2f&c=E,1,Y5zKJKPEh1mBEBqSR-VE9cUKl5y-eyP8BpvmE_5j9ZqW2eJbNphYzrCMBZ-2YuX6d-RRkHI4gQ1FV-cvOeCfRC58uZS9NiToZv2mx7909oCqLvCW_n5hDHeK&typo=1> On 10/9/2023 10:49 AM, Fpdcdesign wrote: Is there a check valve on the floor control assembly? Todd G Williams, PE Fire Protection Design/Consulting Stonington, CT 860-535-2080<tel:860-535-2080> (ofc) 860-554-7054<tel:860-554-7054> (fax) 860-608-4559<tel:860-608-4559> (cell) On Oct 9, 2023 at 11:44 AM, <Ken Wagoner<mailto:k...@parsleyconsulting.com>> wrote: Forumites, I'm working on a multi-story building protected per NFPA 13. As each floor has a separate control valve, is a means to vent trapped air required on each floor? Or is it only required at the highest level of the building? My thinking is that each floor has a separate fire sprinklers system. Any thoughts? Ken Wagoner, SET Parsley Consulting 500 West Mechanic Street Harrisonville, Missouri 64701-2235 Phone: (760) 745-6181 Visit the website<https://linkprotect.cudasvc.com/url?a=http%3a%2f%2fwww.parsleyconsulting.com%2f&c=E,1,Y5zKJKPEh1mBEBqSR-VE9cUKl5y-eyP8BpvmE_5j9ZqW2eJbNphYzrCMBZ-2YuX6d-RRkHI4gQ1FV-cvOeCfRC58uZS9NiToZv2mx7909oCqLvCW_n5hDHeK&typo=1> _________________________________________________________ SprinklerForum mailing list: https://lists.firesprinkler.org/list/sprinklerforum.lists.firesprinkler.org<https://lists.firesprinkler.org/list/sprinklerforum.lists.firesprinkler.org> To unsubscribe send an email to sprinklerforum-le...@lists.firesprinkler.org<mailto:sprinklerforum-le...@lists.firesprinkler.org> _________________________________________________________ SprinklerForum mailing list: https://lists.firesprinkler.org/list/sprinklerforum.lists.firesprinkler.org<https://lists.firesprinkler.org/list/sprinklerforum.lists.firesprinkler.org> To unsubscribe send an email to sprinklerforum-le...@lists.firesprinkler.org<mailto:sprinklerforum-le...@lists.firesprinkler.org> _________________________________________________________ SprinklerForum mailing list: https://lists.firesprinkler.org/list/sprinklerforum.lists.firesprinkler.org<https://lists.firesprinkler.org/list/sprinklerforum.lists.firesprinkler.org> To unsubscribe send an email to sprinklerforum-le...@lists.firesprinkler.org<mailto:sprinklerforum-le...@lists.firesprinkler.org> _________________________________________________________ SprinklerForum mailing list: https://lists.firesprinkler.org/list/sprinklerforum.lists.firesprinkler.org<https://lists.firesprinkler.org/list/sprinklerforum.lists.firesprinkler.org> To unsubscribe send an email to sprinklerforum-le...@lists.firesprinkler.org<mailto:sprinklerforum-le...@lists.firesprinkler.org>
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