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Installing a new water heater

Learn about the legal and safety standards you need for your water heater project.


Where to install your water heater

You must install your water heater in an accessible location. A minimum of 24-inch continuous width is required for access. You may put the water heater in the garage, but you must protect it. Place a fixed barrier like a metal post in the cement between the water heater and where your car would park.

Earthquake preparedness

You must protect your water heater in case of an earthquake by placing seismic bracing on the tank. The bracing must be 2, 20-gauge sheet metal straps. 1 strap must be on the upper 1/3 of the tank and the other on the lower 1/3 of the tank. Approved seismic bracing kits for water heaters are available at many retail outlets.

Expansion tanks

If your water is on a closed system (the water can flow into your building but not out), an expansion tank or other approved thermal expansion device must be installed on your water system. The expansion tank is to hold water that can't be held in the water heater after it expands when it gets hot. If there were no expansion tank, the hot water would be released through the pressure relief valve.

Temperature and pressure relief valves

The temperature and pressure relief valve is a valve that allows pressure to be released if the water heater gets too hot. The valve connects to a pipe that runs to an approved termination point. The pipe must run the water via gravity to the outside or to an approved drain. Always follow the manufacturer's installation instructions regarding location of the temperature and pressure relief valve.

Gas water heaters

There are additional requirements for gas water heaters. If a gas water heater does not get enough combustion air the flame cannot burn to heat the water. If the installed venting is less than what is needed, dangerous carbon monoxide gas can build up causing illness and even death.

It is prohibited for a gas water heater other than those as "direct vent type" to be installed in a bedroom or bathroom unless meeting special criteria. Check for local requirements.

To have a gas water heater, you will need a supply of gas. If you are going to install gas piping or change the gas piping you already have, you must get a separate gas-piping permit. The gas piping must not block the removal of the tank. Always follow the manufacturer's installation instructions.