Section 29-232-64 - Blow-off piping(a) The construction of the setting around each blow-off pipe shall permit free-expansion and contraction. Careful attention shall be given to the problem of sealing these setting openings without restricting the movement of the blow-off piping. All blow-off piping, when exposed to furnace heat, shall be protected by fire brick or other heat resisting material, so constructed that the piping may be readily inspected. Each boiler shall have a blow-off pipe, fitted with a manually operated valve or cock, in direct connection with the lowest water space. Cocks shall be of the gland or guard type and suitable for the pressure allowed. The use of globe valves or automatically controlled electric blow-off valves shall not be permitted. When the maximum allowable working pressure exceeds one hundred psig, each blow-off pipe shall be provided with two valves or a valve and cock, such valves and cocks to be of the extra heavy type, one of which shall be of the slow-opening type.(b) On a boiler having multiple blow-off pipes, a single master valve may be placed on the common blow-off pipe from the boiler in which case only one valve on each individual blow-off is required. In this case either the master valve or the individual valves or cocks shall be of the slow-opening type. When the maximum allowable working pressure exceeds one hundred psig, blow-off piping shall be extra heavy from the boiler to the valve or valves, and shall be run full size without use of reducers or bushings. The piping shall be extra heavy wrought iron or steel and shall not be galvanized. All fittings between the boiler and blow-off valve shall be steel or extra heavy fittings or malleable iron. In case of renewal of blow-off pipe or fittings, they shall be installed in accordance with the regulations for new installations.Conn. Agencies Regs. § 29-232-64
Effective August 25, 1987