An engineering firm has insisted that a waterflow activation shutdown the HVAC system and cited NFPA 90A: A.6.4.3.
A.6.4.3 Where automatic water sprinklers are provided and zoned to coordinate with the HVAC zones, their water flow switches should initiate devices for the functions described in Chapter 6. Each floor of the building has one HVAC zone and one sprinkler zone (floor control valves). The HVAC system has the appropriate duct detectors and functions. The only instance I have experienced using flow switches for HVAC control is when there is no automatic smoke detection and the flow switch is used to start the smoke control system for that zone. What are your thoughts? Is a waterflow switch required to shutdown an HVAC system on this premise? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe
8 Comments
Dan Wilder
3/30/2023 07:48:41 am
I've only ever used this approach in Casinos, large open areas to start an exhaust cycle within the zone of water flow and the adjacent zones went into supply venting (no AC or Heat) to slow the spread of smoke across large open areas. More recently Data centers to control the CRAC/CRAH units within individual data halls along with the shutdowns of the large HVAC units to prevent over pressurization of the hall or blowing out the dampers.
Reply
Jesse
3/30/2023 08:07:32 am
I'm curious as well. Is there a requirement from the engineering firm that impacts fire-protection other than the provision of a flow switch?
Reply
Glenn Berger
3/30/2023 08:13:48 am
This is a new one for me. You can use the intro paragraph to the Appendix - that the Annex A is not of the NFPA document ...
Reply
Todd E Wyatt
3/30/2023 08:16:01 am
When a Code (IBC) or standard (NFPA 90A) uses “SHOULD”, it “indicates a recommendation or that which is advised but not required.”
Reply
Todd E Wyatt
3/30/2023 08:35:00 am
“A.6.4.3” is part of “Annex A — Explanatory Material” :
Reply
Todd E Wyatt
3/30/2023 09:47:07 am
... regardless IF it uses "SHALL" ... which it does not.
Reply
Brad K
3/30/2023 10:49:11 am
This looks to be a case of the "SHOULD" costs an extra and the "ANNEX A" costs an extra (unless Annex is adopted in amendments by AHJ).
Reply
Chad
3/30/2023 02:41:00 pm
That's a big ol RFI that should sound like:
Reply
Leave a Reply. |
ALL-ACCESSSUBSCRIBESubscribe and learn something new each day:
COMMUNITYTop January '25 Contributors
YOUR POSTPE EXAMGet 100 Days of Free Sample Questions right to you!
FILTERS
All
ARCHIVES
February 2025
PE PREP SERIES |