Hayward H-Series Millivolt Na Mv Pool Heater All models English - Page 11

SECTION 3. INSTALLATION Indoor installation and venting: The following installation and service clearances must be maintained from combustible materials. Indoor Installations* Top - 36" Non-combustible floor Front - Unobstructed Vent - 6" Back - 6" Right side (Water side) - 12" Left side - 6" Figure 12 *Canada outdoor shelters Do not Install In a closet! Do not install an H210 indoor! For alcove installations, the drafthood (DHI) shall be installed so as to be in the same atmospheric pressure zone as the combustion air inlet to the pool heater. Air supply: Indoor installations and outdoor shelters must be provided with adequate combustion and ventilation air vents to assure proper heater operation. These vents must be sized according to the requirements stated in A. and B. below and must never be obstructed when heater is in operation. When air blowers are used in spa/hot tub installations, caution must be observed to insure sufficient combustion air is available to the gas heater for proper combustion. A separate blower air duct is recommended. Equipment located in confined spaces: A. All Air Supply From Inside The Building: The confined space shall be provided with two permanent openings communicating directly with an additional room(s) of sufficient volume so that the combined volume of all spaces meets the criteria for an unconfined space (a space whose volume is not less than 50 cubic feet per 1000 BTUH). The total input of all gas utilization equipment installed in the combined space shall be considered in making this determination. Each opening shall have a minimum free area of 1 square inch per 1,000 BTU per hour of the total input rating of all gas utilization equipment in the confined space, but not less than 100 square inches. See Figure 13. One opening shall be within 12 inches of the top and one within 12 inches of the bottom of the enclosure. B. All Air Supply From Outdoors: The confined space shall be provided with two permanent openings, one commencing within 12 inches of the top and one commencing within 12 inches of the bottom of the enclosure. The openings shall communicate directly, or by ducts, with the outdoors or spaces (crawl or attic) that freely communicate with the outdoors. 1. W hen directly communicating with the outdoors, each opening shall have a minimum free area of 1 square inch per 4,000 BTU per hour of total input rating of all equipment in the enclosure. See Figure 13. 2. W hen communicating with the outdoors through vertical ducts, each opening shall have a minimum free area of 1 square inch per 4,000 BTU per hour of total input rating of all equipment in the enclosure. See Figure 13. 3. W hen communicating with the outdoors through horizontal ducts, each opening shall have a minimum free area of 1 square inch per 2,000 BTU per hour of total input rating of all equipment in the enclosure. See Figure 13. 4. W hen ducts are used, they shall be of the same cross-sectional area as the free area of the openings to which they connect. The minimum dimension of rectangular air ducts shall be not less than 3 inches. ! NOTE: For more detailed methods of providing air for com- bustion and ventilation, refer to latest edition of the National Fuel Gas Code, ANSI Z223.1. Free Area per Btu Requirement 1 sq. in. per 1,000 btu/hr (paragraph A) 1 sq. in. per 2,000 btu/hr (paragraph B-3) 1 sq. in. per 4,000 btu/hr (paragraph B-1) 1 sq. in. per 250 btu/hr (below-ground installation) Total Input (btu/hr) 150,000 200,000 250,000 300,000 350,000 400,000 150,000 200,000 250,000 300,000 350,000 400,000 150,000 200,000 250,000 300,000 350,000 400,000 150,000 200,000 250,000 300,000 350,000 400,000 Combustion Air Free Area Required (sq. in.) 150 200 250 300 350 400 75 100 125 150 175 200 37.5 50 62.5 75 87.5 100 600 800 1000 1200 1400 1600 Ventilation Air Free Area Required (sq. in.) 150 200 250 300 350 400 75 100 125 150 175 200 37.5 50 62.5 75 87.5 100 600 800 1000 1200 1400 1600 Figure 13 9