HEAT TRAP. An arrangement of piping and fittings, such as elbows, or a commercially available heat trap that prevents thermosyphoning of hot water during standby periods.
HEAT TRAP, PIPE CONFIGURED. A pipe configured heat trap is either, as applicable:
1. A device specifically designed for the purpose or an arrangement of tubing that forms a loop of 360 degrees; or
2. Piping that from the point of connection to the water heater (inlet or outlet) includes a length of piping directed downward before connection to the vertical piping of the supply water or hot-water distribution system.
HEATED SLAB-ON-GRADE FLOOR. Slab-on-grade floor construction in which the heating elements, hydronic tubing, or hot air distribution system is in contact with, or placed within or under, the slab.
HEATED WATER CIRCULATION SYSTEM. A water distribution system having one or more recirculation pumps that pump water from a heated water source through a dedicated hot water circulation pipe or piping system.
HIGH SPEED DOOR. A nonswinging door used primarily to facilitate vehicular access or material transportation, with a minimum opening rate of 32 inches (813 mm) per second, a minimum closing rate of 24 inches (610 mm) per second and that includes an automatic-closing device.
HISTORIC BUILDINGS. Buildings that are listed in or eligible for listing in the National Register of Historic Places, or designated as historic under an appropriate state or local law.
HUMIDISTAT. A regulatory device, actuated by changes in humidity, used for automatic control of relative humidity.
HVAC TOTAL SYSTEM PERFORMANCE RATIO (HVAC TSPR). The ratio of the sum of a building's annual heating and cooling load in thousands of Btus to the sum of annual carbon emissions in pounds from energy consumption of the building HVAC systems. Carbon emissions shall be calculated by multiplying site energy consumption by the carbon emission factors from Table C407.1.
[Statutory Authority: RCW
19.27A.020,
19.27A.025,
19.27A.160 and chapter
19.27 RCW. WSR 19-24-040, § 51-11C-20208, filed 11/26/19, effective 7/1/20. Statutory Authority: RCW
19.27A.025,
19.27A.160, and
19.27.074. WSR 16-03-072, § 51-11C-20208, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW
19.27A.020,
19.27A.025 and chapters
19.27 and
34.05 RCW. WSR 13-04-056, § 51-11C-20208, filed 2/1/13, effective 7/1/13.]