§ 14-12-57. Existing installations.

A.

Application of section. This section shall apply to existing heating boilers.

B.

Maximum allowable working pressure in A.S.M.E. Code boilers. The maximum allowable working pressure of a boiler built in accordance with the A.S.M.E. Code shall in no case exceed the pressure indicated by the manufacturer's identification stamped or cast upon the boiler or upon a place secured to it.

C.

Maximum allowable working pressure for non-code riveted boilers. The maximum allowable working pressure on the shell of a noncode riveted heating boiler shall be determined in accordance with the provisions of this article for covering existing installations power boilers, except that in no case shall the maximum allowable working pressure of a steam heating boiler exceed 15 pounds or a hot water boiler exceed 160 pounds at a temperature not exceeding 250 degrees Fahrenheit.

D.

Maximum allowable working pressure for non-code welded boilers. The maximum allowable working pressure of a noncode steel or wrought iron heating boiler of welded construction shall not exceed 15 pounds. For other than steam service the maximum allowable working pressure shall be calculated in accordance with section IV of the A.S.M.E. Code.

E.

Maximum allowable working pressure for noncode cast iron boilers. The maximum allowable working pressure of a noncode boiler composed principally of cast iron shall not exceed 15 pounds for steam service or 30 pounds for hot water service. The maximum allowable working pressure of a noncode boiler having cast iron shell or heads and steel or wrought iron tubes shall not exceed 15 pounds for steam service or 30 pounds for water service.

F.

Fired radiators. A radiator in which steam pressure is generated at a pressure of 15 pounds or less is considered a low pressure boiler.

G.

Procedure if operation unsafe at previously approved pressure. If in the judgment of the inspector a steam heating boiler is unsafe for operation at the pressure previously approved, the pressure shall be reduced, proper repair made or the boiler retired from service.

H.

Safety valves. Each steam heating boiler shall be provided with one or more officially rated safety valves of the spring-pop type adjusted and sealed to discharge at a pressure not to exceed 15 pounds per square inch. The installation, size and capacity of the safety valves shall conform to the requirements of the A.S.M.E. Heating Boiler Code.

I.

Water relief valves. Each hot water heating boiler shall have at least one officially rated pressure relief valve set to relieve at or below the maximum allowable working pressure of the boiler. Each hot water supply boiler shall have at least one officially rated pressure temperature relief valve of the automatic-reseating type set to relieve at or below the maximum allowable working pressure of the boiler. The installation, size and capacity of the relief valves shall conform to the requirements of the A.S.M.E. Heating Boiler Code.

J.

Steam gauge. Each steam boiler shall have a steam pressure gauge connected to the steam space of the boiler itself or on steam pipe near the boiler. The graduations of the steam gauge shall not be less than 15 pounds nor more than 30 pounds.

K.

Water gauge glass and gauge cocks. Each steam boiler shall have at least one water gauge glass with the lowest visible part above the heating surfaces in the primary combustion chamber. When, in the judgment of an inspector, the heating surfaces above the low water line may be injured by contact with gases or high temperature the water gauge glass shall be raised until the lowest visible part of the gauge glass is above such heating surface.

Each steam boiler shall have two or more gauge cocks located within the visible length of the water gauge glass, except when such boiler is provided with two water gauge glasses.

L.

Stop valves and check valves. If a boiler may be closed off from the heating system by closing a steam stop valve, there shall be a check valve in the condensate return line between the boiler and the system.

If any part of a heating system may be closed off from the remainder of the system by closing a steam stop valve, there shall be a check valve in the condensate return pipe between the boiler and the system.

M.

Feed water connections. Feed water connections shall be independent of any water gauge connections and be made to the condensate return pipe or reservoir of the condensate return pump. There should be a stop valve and a check valve in the feed water line at the boiler.

N.

Return pump. Each condensate return pump where practicable shall be provided with an automatic water level control set to maintain the water level within the limits of two gauge cocks.

O.

Repairs and renewals of fittings and appliances. Whenever repairs are made to fittings or appliances or it becomes necessary to replace them, the work must comply with the provisions of this chapter for new installations.

P.

Stamping of existing heating boilers. Each steel heating boiler shall be stamped with a serial number of the city, followed by the letters "MFS," such letters and figures to be not less than 5/16 inch in height. The stamping shall not be concealed by flagging or paint and shall be exposed at all times. Each cast iron heating boiler shall have securely attached to the front of the boiler a metal tag not less than one inch in height, which shall have the serial number of the city stamped thereon.

(Code 1967, § 45-87; Code 1985, § 42-92; Ord. No. 1427, § 1(4), (5), 8-29-1972)