Sprinkler proximity to AC diffuser etc
Sprinkler proximity to AC diffuser etc
(OP)
I'm having trouble finding anything in NFPA13 regarding heat zones etc. for QR or SR SSP pendants
Any help would be appreciated, thanks
Any help would be appreciated, thanks





RE: Sprinkler proximity to AC diffuser etc
RE: Sprinkler proximity to AC diffuser etc
I don't think there is any rule that stops you from putting a sprinkler next to a diffuser (although it will likely take longer to go of in a fire with cold air being blown on it).
RE: Sprinkler proximity to AC diffuser etc
Then sprinklerdesigner2 referred his comment to NFPA 13:
Distance from sprinkler to heat sources
AZsprink needs to elaborate a little more so we can properly comment on his question.
RE: Sprinkler proximity to AC diffuser etc
I know that most tyco residential heads have to be at least 2 ft. from vertical AC diffusers and 3 ft. from the front and 2ft. from the side of horizontal diffusers (according to the TYCO residential design guide)
I wasn't sure if the requirements are different for commercial heads, looks like they are, for commercial heads you can be 1 ft. from vert. diffuser. "maybe residential heads are more sensitive to temp. changes than commercial heads"
Thanks
RE: Sprinkler proximity to AC diffuser etc
RE: Sprinkler proximity to AC diffuser etc
I suspect (and this is purely my opinion) the increased distance is necessary because residential sprinklers have an RTI <= 50. Most likely the manufacturers are concerned with HVAC air flow interrupting the hot gas plume and ceiling gas layer during the fire's growth from incipent to pre-flashover.
RE: Sprinkler proximity to AC diffuser etc
RE: Sprinkler proximity to AC diffuser etc
Perhaps NFPA should be concerned about interupting the gas plume the way you described, however the way NFPA 13 is written, the requirement only addresses diffusers used for heating not for cooling.
The requirement seems to address unwanted discharge of sprinklers caused by overheat, but doesn seem to address reduced response time caused by blowing cold air on a sprinkler as diffusers that only have cold air are exempt.
RE: Sprinkler proximity to AC diffuser etc