How to Install a Gas Water Heater

installing a gas water heater hot water outlet

Without water heaters, what would separate civilized people from animals? Hot water is one of the essential comforts in the United States. If your water heater is out in December, you're going to feel it, even in the sunbelt. A water heater tank can be expensive to replace. If you are looking to do the job yourself, a novice can accomplish it. Here, you will learn how to install a gas water heater in an afternoon. Before getting started installing a gas water heater yourself, ask this question:

Do I Need to Solder the Connections?

Will I need to know how to use a torch for soldering? Water heaters can connect to various pipe types. Plastic water pipe needs to have water flex connections at least 18" long to keep from overheating the pipe. These water flexes are made of copper and have threaded connections on both sides, so no soldering is required in this instance. It is possible to have water to flex connections that are solder only on one end and threaded on the other (typically, if you are tying into an existing copper line). If you need to learn how to solder water heater pipes, we also have a resource for that.

The pressure relief valve outlet may require some soldering, but that can typically be run with PVC pipe and a male adapter instead (the valve threads into the water heater, so no soldering there).

Gas Hot Water Heater Installation in 8 Steps

Whether you are interested in installing a propane water heater, or more commonly, a natural gas water heater, the steps will be very similar and will both be outlined here:

Move your tank into position.
Ensure that the drain valve is closed tight.

installing a gas water heater flex connection

Connect the water supply line with the shutoff valve to your water heater inlet (it should be marked as cold or have a blue ring around it). Again, you may have to solder, but maybe not. We recommend using Teflon tape for better connections with the supply line and the water heater. Connect to the hot water line out.
Connect the Gasflex to the water heater valve on the front of the heater. The side that hooks into the heater will require Teflon tape or pipe dope, but the connection on the gas flex side is a "flared" connection and does not.
Connect the tank to the ductwork leading to the draft hood that vents out the water heater. This may require the use of a 1/4 or 5/16 inch socket, depending on your heater brand.
Turn on the water supply line, and the tank should fill up. If you feel like it's near full, check a faucet on your top floor. If there is no steady flow of water, your tank is not yet complete (full or not, expect some spitting and hissing as the air in the water lines is replaced with water).
Double-check that your water heater valve is set at the off position, and turn your gas valve on.
Follow the instructions for setting the Pilot. Some are manual; others are automatic. Ignite the pilot light, set the temperature (120 degrees or so), and you're in business!

For a visual tutorial, try this AO Smith how-to video.

Turn to the Water Heater Experts

Hopefully, this how to install a gas water heater tutorial guide has been helpful. If you are looking for water heater parts, or a specific brand of water heater (Bradford White, for example), then you are in the right place. If you have any questions about your project or water heaters in general, please contact us.