Ah, standard temperature rated heads in walk-in coolers or freezers. You have bumped up against an interest of mine. I sent photos and stories of false operations to various manufacturers for a number of years. Answer back was consistently of a flavor "You're the only one we've ever heard complain about these, kid. Go away".
I started sending them to UL. After a couple years they became interested and helpful. All evaporators, or blowers to non-refer folks, in freezers, and many in low temp coolers go through a defrost cycle. Look at them next time your in a freezer. They will have a small drain line (heat taped, insulated) from the evaporator to out of the space. The go through a heat cycle to remove the frost on the coils. It is not to defrost the room. Immediately after the defrost cycle the room is by definition above the set point. They go in to cold cycle. The first head in front, and head behind the evaporator are exposed to this cycle several times daily. If of types of dry pendent heads manufactured prior to changes of a number of years ago they fail. Link, bulb, pick you manufacturer. I know of one loss time injury associated with these failures. 3-4 inches of ice on floor is common result of head failure. Employee was using spud to remove ice. Slipped, dislocated shoulder. Double interlock systems of course only resulted in temporary loss of protection, after hours service call. Code and head manufacture, and installation changes, have to my observation been effective at preventing this type of false operation. High temperature heads may be per FM, or for reduced area. But the only alternative is intermediate temp heads where evaporators go through defrost cycle. Expect them to all go through defrost cycle and you can't go wrong. It is a non-cost improvement. bv ----- Original Message ----- From: "Bob" <bob@ firebyknight .com> To: sprinklerforum @lists. firesprinkler .org Sent: Monday, July 8, 2013 10:07:21 AM Subject: RE: High Temp Heads in Cooler Depending on circumstance, it could exceed 150d which is the max temp for a 200d head. Bob Knight, CET III 208-318-3057 www . firebyknight .com -----Original Message----- From: sprinklerforum -bounces@lists. firesprinkler .org [ mailto : sprinklerforum -bounces@lists. firesprinkler .org] On Behalf Of Forest Wilson Sent: Monday, July 08, 2013 10:29 AM To: sprinklerforum @lists. firesprinkler .org Subject: Re: High Temp Heads in Cooler There is no way an auto defrost will reach 286* Sent from my iPhone On Jul 8, 2013, at 12:13 PM, "Steve Leyton " < steve @ protectiondesign .com> wrote: > Also if there's storage. We're working with two large 26' high > walk-ins currently. > > Steve > > Richard Carr < RCarr @ coxfire .com> wrote: > > Yes, they have a defrost mode that will pop a head of 155 deg. > > Richard Carr, SET > Branch Manager > Cox Fire Protection, Inc > 6555 Grace Lane. > Jacksonville, Fl. 32205 > rcarr @ coxfire .com > 904-781-8227 > > > -----Original Message----- > From: sprinklerforum -bounces@lists. firesprinkler .org > [ mailto : sprinklerforum -bounces@lists. firesprinkler .org] On Behalf Of > Forest Wilson > Sent: Monday, July 08, 2013 11:48 AM > To: SprinklerForum > Subject: High Temp Heads in Cooler > > Is there any rational reason to install high temperature heads in a > walk in cooler/ freezer? > > Sent from my iPhone > _______________________________________________ > Sprinklerforum mailing list > Sprinklerforum @lists. firesprinkler .org > http ://lists. firesprinkler .org/ listinfo . cgi / sprinklerforum > -firesprinkl > er > .org > _______________________________________________ > Sprinklerforum mailing list > Sprinklerforum @lists. firesprinkler .org > http ://lists. firesprinkler .org/ listinfo . cgi / sprinklerforum > -firesprinkl > er.o > rg > > _______________________________________________ > Sprinklerforum mailing list > Sprinklerforum @lists. firesprinkler .org > http ://lists. firesprinkler .org/ listinfo . cgi / sprinklerforum > -firesprinkl > er.org _______________________________________________ Sprinklerforum mailing list Sprinklerforum @lists. firesprinkler .org http ://lists. firesprinkler .org/ listinfo . cgi / sprinklerforum - firesprinkler .org ----- No virus found in this message. Checked by AVG - www .avg.com Version: 2013.0.3349 / Virus Database: 3204/6473 - Release Date: 07/08/13 _______________________________________________ Sprinklerforum mailing list Sprinklerforum @lists. firesprinkler .org http ://lists. firesprinkler .org/ listinfo . cgi / sprinklerforum - firesprinkler .org _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
