The installation of all water heaters shall comply with the Ohio Building Code, Chapter BB-51 (Plumbing), Sections BB-51-30 and BB-51-31, as follows:
(a) Equipment used for heating water or storing hot water, except hot water heating boilers, shall be protected by approved safety devices in accordance with one of the following methods:
(1) A separate pressure relief valve and a separate temperature relief valve;
(2) A combination pressure and temperature relief valve; or
(3) A separate pressure relief valve and an energy cut-off device.
(b) Heaters not in excess of 200,000 BTU input, pressure, temperature, vacuum, relief valves or automatic gas shut-off devices meeting the requirements of the standard A.N.S.I. (formerly A.S.A.) Z21.22 under the conditions of BB-51-05(A) and cut- off devices under ULI listings are acceptable as approved devices.
(c) Heaters in excess of 200, 000 BTU input shall be equipped with pressure relief valves bearing the American Society of Mechanical Engineers (ASME) pressure steam rating. Combination temperature and pressure relief valves on heaters in this capacity range shall have the temperature portion of the valve rated by the A.N.S.I. (formerly A.S.A.) temperature steam rating method. The temperature rating of the combination valve shall be used in sizing the valve unless the ASME steam pressure rating is lower.
(d) Relief valves having rating capacities in excess of 15,000 BTU, but not exceeding 200,000 BTU, and pressure relief valves not limited in application, shall have inlet and discharge connections not smaller than three-fourths of an inch NPT. Relief valves rated at 15,000 BTU and less than 15,000 BTU may have one-half inch NPT connections.
(e) Pressure relief valves shall be installed in the cold water supply to the tank, except where water conditions are such as to warrant its installation in the tank or hot water supply line.
(f) Temperature relief valves and energy cut-off devices shall be mounted so that the temperature-sensing element of the immersion-type is located in the water within the upper six inches of the tank and against the exterior of the tank and within six inches of the top thereof for surface contact types.
(g) Storage type heaters with copper storage tanks shall be equipped with a vacuum relief valve to relieve at a pressure in the tank of not more than one inch mercury column below atmospheric pressure.
(h) Relief valves shall be installed on or as near as possible to the heater or tank which they serve and no check or shut-off valve shall be installed between the relief valve and the tank or heater which it serves, and no shut-off valve shall be permitted in the discharge pipe from the relief valve.
(i) The discharge from relief valves shall be piped, undiminished in size, to a safe location for free discharge or may be indirectly connected to the drainage system.
(j) All relief valves and devices shall have their ratings plainly stamped, cast or etched on the device or on a permanent nameplate securely affixed to the device.
(k) Storage tanks for domestic hot water shall have clearly and indelibly stamped in the metal, or so marked upon a plate welded thereto, or otherwise permanently attached, the maximum allowable working pressure. Such markings shall be placed in an accessible position on the outside of the tank so as to make inspection or reinspection readily possible. ASME is, under the conditions of Section BB-51-03, the approved standard for the manufacture, design, properties and quality of hot water storage tanks.
(l) All gas-fired water heaters must be American Gas Association (AGA) approved. All vents on gas-fired water heaters must be Masonry, Type B, Type BW, or equivalent.
(m) A plumbing permit shall be issued by the Mayor for each installation or replacement of equipment used for heating or storing hot water. The fee for such permit shall be three dollars ($3.00). (Ord. 1049. Passed 12-18-67.)