Grill The Fire Expert

AHJ Wants Out of the Closet

Q: A sprinkler monitoring system is to be installed at a Sacramento , Calif. apartment building that has no common/public area. The FACP is to provide monitoring for the waterflow alarm switch and several valve supervisory switches. The local AHJ is asking the equipment to be kept 60 ° F to 80 ° F and 85% humidity, which is also recommended by the manufacturer. Maintaining this temperature range for the panel or the annunciator will be hard. There is a padlocked utility/storage closet that I can use for the fire alarm panel, located on the side of the building. It has an outside entrance but is neither heated nor air conditioned. I thought I'd install a remote annunciator on the outside of this room so the FD will have access to it, and use an STI enclosure. I'm considering installing the FACP inside the closet using a NEMA 4 enclosure. I also thought about designating one unit as a manager unit and install the FACP within it, but I'm still stuck with the annunciator issue. Use of a rated enclosure or converting the closet to house the FACP seem to be my only viable options. Our Sacramento weather is not extreme. Is the AHJ correct or unreasonable?


A: You have two problems involving the listed temperature limits of equipment. As for the lower temperature limit, your claim that “ Sacramento weather is not extreme” may not be correct. Back in 1990 you had 15 days of below-freezing weather, and have averaged 4.7 days of freezing temperatures every year from 1971 to 2000. (See NOAA Technical Memorandum NWS WR-272.) Neither the keypad-annunciator nor the FACP is permitted by UL/NFPA to be installed where the temperature is freezing or exceeds 120° F. The NEMA Type 4 enclosures “are intended for indoor or outdoor use primarily to provide a degree of protection against windblown dust and rain, splashing water, and hose-directed water; undamaged by the formation of ice on the enclosure.” However, they do not contain little furnaces or tiny air conditioners to keep the electronics within the range limits specified by UL/NFPA. The lower temperature limit may not be a problem for the FACP if you do as you suggested and place it in a manager's unit, under a system type smoke detector. Access to this FACP shouldn't be an issue, as long as the annunciator is available. Indeed, STI makes a Heated Polycarbonate Enclosure to keep your annunciator from freezing. If it isn't installed in direct sunlight, exceeding the 120° upper limit imposed by UL/NFPA, then it shouldn't be a problem, either. I'd try putting the annunciator in the common utility closet if it is vented to keep heat from exceeding 120°. Placing it on the inside wall, lower down, will also help. I'd also install the manual pull in this closet.

BTW, the reason prompt access to the annunciator shouldn't be an issue is because there is only one alarm zone—the sprinkler waterflow. Because the sprinkler system uses a watermotor gong, there will be no FACP connected to audible appliances for the FD to silence. Placing a padlock on the closet door will allow FD access for re-setting the system after the sprinkler emergency has been dealt with. (A new hasp may be needed!)

In the end, this is a building construction issue that the owner and code official may need to work out. Technicians encounter similar construction issues with buildings designed with a lot of ground floor glass, making it impossible to place a manual pull box within five feet of the exit. Offer some variation of the above installation, and if it isn't acceptable to the code official, let him impose the solution on the owner. Code officials are required to inform you, in writing, of how a violation may be remedied.


Greg Kessinger, SET, CFPS, president of an alarm installing company since 1981, teaches NICET training classes to fire alarm system designers and installers and continuing education seminars for Ohio 's fire alarm inspectors. You can reach him at 888-910-2272; e-mail:; or visit his website at

This content continues onto the next page...