For a gas-fired direct vent water heater, the bottom of the vent terminal and air intake must be located at least how many inches above grade?

For a gas-fired direct vent water heater, the bottom of the vent terminal and air intake must be located at least 12 inches above grade to ensure safe and efficient operation. This requirement is in place to prevent the possibility of snow, debris, or water from blocking the vent, which could lead to improper combustion or backdrafting of exhaust gases.

Maintaining this height from grade helps to minimize the risks associated with potential flooding or accumulation of materials that could obstruct the flow of air necessary for combustion, thereby promoting the efficient functioning of the water heater and enhancing user safety. The specific height of 12 inches strikes a balance between safety considerations and practical installation requirements, ensuring that the venting system performs as designed without interference from environmental factors.