Current through Register Vol. 47, No. 11, December 11, 2024
Rule 875-92.8 - Boiler feedingThis rule applies to power boilers installed prior to July 1, 1983.
(1) Each boiler shall have a feed supply that will permit it to be fed at any time while under pressure. A boiler having more than 500 square feet of water-heating surface shall have at least two means of feeding, one of which shall be an approved feed pump, injector, or inspirator. One source of feed is directly from the water main. Boilers fired by gaseous, liquid, or solid fuel in suspension may be equipped with a single means of feeding water provided means are furnished for the immediate shutoflf of heat input prior to the water level reaching the lowest permissible level. The feedwater shall be introduced into the boiler in such a manner that it will not be discharged close to riveted joints of shell or furnace sheets, directly against surfaces exposed to products of combustion, or directed to surfaces subject to radiation from the fire. The feed piping to the boiler shall be provided with a check valve near the boiler and a stop valve between the check valve and the boiler.(2) When two or more boilers are fed from a common source, there shall also be a valve on the branch to each boiler between the check valve and source of supply. Whenever a globe valve is used on feed piping, the inlet shall be under the disk of the valve. In all cases where returns are fed back to the boiler by gravity, there shall be a check valve and stop valve in each return line. The stop valve shall be placed between the boiler and the check valve, and both shall be located as close to the boiler as is practicable.Iowa Admin. Code r. 875-92.8