Indiana Administrative Code › Title 675 - FIRE PREVENTION AND BUILDING SAFETY COMMISSION › Article 30 - INDIANA BOILER AND PRESSURE VESSEL RULES › Rule 10 - Existing Installations of Heating Boilers › Section 10-13 - Relief valves for hot water heating or supply boilers; settings; dimensions; relief capacity

Current through July 10, 2024
Authority: IC 22-13-2-8
Affected: IC 22-15-6
Sec. 13.
(a) Each
				hot water heating or hot water supply boiler shall have one (1) or more relief
				valves of the spring-loaded type without disk guides on the pressure side of
				the valve. The valves shall be set to relieve at a pressure at or below the
				MAWP of the boiler and so arranged that they cannot be reset to relieve at a
				pressure higher than the MAWP of the boiler. The capacity of water relief
				valves that have not been officially rated in accordance with the ASME
				B&PVC shall not be taken into consideration in determining the required
				relieving capacity.
(b) Each relief
				valve shall have a substantial device that will positively lift the disk from
				its seat at least one-sixteenth (1/16) inch when there is no pressure on the
				boiler.
(c) The seats and disks of
				relief valves shall be of material suitable to resist corrosion and withstand
				the preliminary test prescribed in the ASME B&PVC for low pressure heating
				boilers. No materials liable to fail due to deterioration or vulcanization when
				subjected to any temperature not exceeding two hundred seventy-five (275)
				degrees Fahrenheit shall be used for any part.
(d) No relief valve shall be smaller than
				three-fourths (3/4) inch nor larger than four and one-half (41/2) inches
				standard pipe size. The inlet opening shall have an inside diameter equal to,
				or greater than, the seat diameter. In no case shall the minimum opening
				through any part of the valve be less than one-fourth (1/4) inch diameter or
				its equivalent area.
(e) The
				relieving capacity in pounds per hour shall be determined from the maximum Btu
				output at the boiler nozzle obtained by the firing of any fuel for which the
				unit is designed. In many cases a greater relieving capacity than the minimum
				specified will be necessary. In every case, the requirements of subsection (g)
				shall be met.
(f) When operating
				conditions are changed or additional boiler heating surface is installed, the
				valve capacity shall be increased, if necessary, to meet the new conditions and
				be in accordance with subsection (g). The additional valves required by changed
				conditions may be installed on the outlet pipe providing there is no
				intervening valve, nor any other branching pipes between valve and
				boiler.
(g) Relief valve capacity
				for each boiler shall be such that with the fuel-burning equipment installed,
				pressure cannot rise more than twenty percent (20%) above the highest maximum
				allowable working pressure for pressure up to and including thirty (30) psig
				and ten percent (10%) for pressures over thirty (30) psig.
Transferred from the Boiler and Pressure Vessel Rules Board
					 ( 680 IAC 2-10-13 ) to the Fire Prevention and Building Safety Commission ( 675
					 IAC 30-10-13 ) by P.L. 249-2019,
					 SECTION
					 15, effective July 1,
					 2019.