The provisions of this chapter shall govern the materials, design and installation of water heaters and the related safety devices and appurtenances.
Exception: Water heaters shall comply with the “Ohio Boiler and Pressure Vessels rules,” Chapters 4101:4-1 to 4101:4-10 of the Administrative Code, when any of the following limitations are exceeded:
- Heat input of two hundred thousand BTU per hour;
- Water temperature of two hundred ten degrees Fahrenheit;
- Nominal water containing capacity of one hundred twenty gallons.
Elevation of water heater ignition sources and mechanical damage protection requirements for water heaters shall be in accordance with the mechanical code and the International Fuel Gas Code.
Exception: Elevation of the ignition source is not required for appliances that are listed as flammable vapor ignition resistant.
The discharge piping serving a pressure relief valve, temperature relief valve or combination thereof shall:
- Not be directly connected to the drainage system.
- Discharge through an air gap located in the same room as the water heater.
- Not be smaller than the diameter of the outlet of the valve served and shall discharge full size to the air gap.
- Serve a single relief device and shall not connect to piping serving any other relief device or equipment.
- Discharge to the floor, to the pan serving the water heater or storage tank, to a waste receptor or to the outdoors.
- Discharge in a manner that does not cause personal injury or structural damage.
- Discharge to a termination point that is readily observable by the building occupants.
- Not be trapped.
- Be installed so as to flow by gravity.
- Not terminate more than 6 inches (152 mm) above the floor or waste receptor.
- Not have a threaded connection at the end of such piping.
- Not have valves or tee fittings.
- Be constructed of those materials listed in Section 605.4 or materials tested, rated and approved for such use in accordance with ASME A112.4.1.