10-10393 - Laserfiche WebLink

Browse Search

Chapter 3 – System Design Page 3 -19 REV. 1 DETECTOR PLACEMENT . Detectors are required over cooking appliances and in the 1L duct(s) of protected ventilation hoods. Detectors shall be located in the plenum area of the ventilation hood. \ a Exhaust Duct(s). Each exhaust duct must have at least one (1) detector _ installed in the duct entrance, located in the air stream of the cooking vapors at a maximum of 12 feet (3.7 m) into the , • duct. See Figure 3 -23. . 1 I. Figure 3 -23a. 5 ......... s. — 10= = 000208 Cooking Appliance(s). 12 FT. Each cooking appliance with a continuous cooking surface MAXIMIUM m) not exceeding 48 In. x 48 in. (122 x 122 cm) shall be protected by one (1) detector. Cooking appliances with a continuous cooking surface exceeding 48 in. x 48 in. (122 x 122 cm) shall be protected by one (1) detector per 48 in. x 48 In. (122 x 122 cm) cooking area. Detectors used for • cooking appliances must be located above the protected —__I----e( o . lin appliance toward the exhaust duct side of the appliance. The detector should be located in the alr stream of the appliance to enhance system response time. Figure 3 -23. If a cooking appliance is located under a duct opening where 008884PC a detector has been mounted, it Is not necessary to utilize 1. an additional detector provided the duct detector is not more NOTICE than 12 in. (31 cm) into the duct opening. if two (2) appli- When gas appliances are used and the flue gases from ances are located under a duct opening where a detector has been mounted, it Is not necessary to utilize an additional the burner are exhausted into the duct, the detector must detector provided the duct detector is not more than 12 in. be kept out of the air stream of these exhaust gases. These gases can be very hot and could actuate the (31 cm) into the duct opening. See Figure 3 -24. system unnecessarily. Duct openings that are long and narrow or large enough to require multiple duct nozzles may require additional detectors. (A_1 <e) (c� Electrostatic Precipitator. If an electrostatic precipitator Is located at or near the base of the exhaust duct, it is necessary to locate a detector below the precipitator, at the base of the duct, and also locate one in the duct, just above the precipitator. See Figure 3 -23a. When installing the detector bracket and system conduit, make APPLIANCE APPLIANCE APPLIANCE APPLIANCE certain they do not interfere with the operation of the COVERED COVERED COVERED COVERED precipitator. BY BY BY DETECTOR DETECTOR DETECTOR DETECTOR A R 6 C Figure 3 -24. Proper Detector Placement. 002943PC ULEX 3830 PN551274(3) August 1, 2005