Water heaters are appliances that heat water for your home. However, they won’t last forever. Water heaters can last between 8 and 12 years. You will need a gas supply, cold-water supply, and a flue connection in order to divert harmful combustion gasses. This guide will show you how to install a gas heater tank in your house.

Note: Tankless gas water heaters require different installation requirements. For specific requirements, make sure you consult your owner’s manual.

Considerations for Installation

Gas piping and combustion gas venting are required to replace tank-type gas heaters. If you don’t know how to connect gas lines and make vent connections, it is best to hire a professional plumber. It can be dangerous to learn how to replace a gas heater. Get in touch with our water heater installation team to schedule an appointment today.

• Before buying a new tank, make sure you check the labels to verify the size and energy specifications. New energy code requirements apply to water heaters made after 2015. These tank-type water heaters are more insulation. These units are now larger than models made before 2015.
• Take measurements of the space where the old water heater will fit. Check the specifications of the new model if your water heater was made before 2015.
• Local plumbing codes may have special requirements for water heaters. Check that your gas hot water installation meets the requirements of your water heater type and your local plumbing codes.

Drain the Tank

Start the installation of a gas water heater by draining the tank.

• Turn off the water supply for the water heater. Turn the control valve on the water heater to “off”. Next, turn off the gas supply valve for the water heater.
• Turn on the nearest hot-water faucet and let it run until the water cools. This will drain the unit safely and without requiring hot water. This will speed up the draining of your tank.
• Attach a gardenhose to the drain valve. The tank can be emptied into buckets, a basement drain, or a suitable place outside. Extreme caution is required if you drain the tank with the water still hot. Use a heat-resistant hose.

Disconnect the Gas and Water Lines

Next, disconnect the water and gas lines from the old heater.

• Once you have confirmed that the gas supply has been shut off, you can disconnect the gas line with two pipe wrenches. If the gas supply pipe is made of black iron, disconnect the gas line at its union fitting. If the gas supply pipe is flexible, disconnect at the flare fitting. The union fitting is usually installed right after the gas valve feeding the water heater.
• Two adjustable wrenches (or pipe wrenches) are used to disconnect the water lines from the tank. To cut the pipe if the piping is already soldered in place, you can use a tubing cutter. Before cutting the pipe, clean it with a sanding paper. This will make it easier later to prepare for the solder connections.
• Any gas piping attached to the gas valve of an old water heater should be removed. If the supply is made from black iron pipe, you can keep the tank tee or sediment trap intact. You can reuse the leg connecting to the union later.
• The old hot water heater’s overflow pipe, pressure release valve and pressure relief valve should be removed. It will be reinstalled later on the new unit.

Take out the gas exhaust and the water heater

Before replacing a gas water heater, the final step is to remove the exhaust gas from the vent cover. This vent removes harmful combustion gases from your home and is vital. These gases are carbon monoxide.

• Use a screwdriver/nut driver to remove the screws that connect the vent pipe and the water heater.
• You can leave the venting intact, but make sure to inspect for damage or rust. If the condition is poor, replace the flue pipe.
• The old water heater should be removed. The older units can accumulate sediment over time so be prepared for it to weigh more than a new unit. A helper or an appliance doll may be needed.
• Get rid of your old water heater. For more information about how to dispose of it, contact your local sanitation company. If you hire a professional to install your water heater, they should remove it as part of their service.
• Clean the area where the water heater was.

How to Install a Gas Water Heating System

Now it’s time to install the gas water heater. You can replace an old water heater, or install a new one. This will ensure that adequate ventilation is achieved.

• Place the water heater in a position that allows easy access to the burners and controls. Follow all manufacturer’s instructions and comply with local water heater code requirements. You must ensure that the location is clear of combustible materials.
• To level the water heater, use a leveling tool and plastic shims.
• Use a screwdriver to connect the flue cap to the gas exhaust port. Hot water heaters that are 55 gallons or larger are more efficient and can not be vented to a chimney. These units should be vented to the exterior using non-metallic, plastic vent pipe. Follow the manufacturer’s instructions for venting if you need to replace this tank.

Tip: If the heater ever leaks, place it in a drain pan to catch any water.

Install the Heat Trap Fittings & Water Line Connections

Attach the heat trap fittings to your water line connections. Your water heater’s efficiency is improved by heat trap fittings. They stop hot water from leaving the tank, and prevent cold water from entering the tank when it isn’t in use.

• Use thread seal tape to wrap the threads of heat trap fitting pipes. These fittings can be oriented. Look for the arrows to indicate the direction of installation. Water will not flow correctly if it isn’t installed correctly.
• Attach the blue-coded fitting at the cold-water outlet. The arrow should face into the water heater.
• The red fitting should be attached to the hot water outlet. The arrow should point away from the heater.
• Use a pipe wrench to tighten the fittings or adjust pliers.
• Take measurements and make the necessary cuts to the water line connections.
• Dry fit all copper parts before you sweat the rest. Make sure to heat any threaded copper fittings first. Allow them to cool down before you attach them to the heat trap fittings. After you have put the pieces together, separate them. Clean each joint as well as the pipe’s end. To do this, use a sanding cloth and a pipe fitting toothbrush.
• Apply flux to the fittings. Use a propane torch to assemble and solder.
• Connect the water line.
• Attach the pressure relief valve. Attach the pressure relief valve to the tank by wrapping the threads in thread seal tape and screwing it on.
• The drain line for the valve should be connected to the tank that was previously used. Attach the thread seal tape to the valve.

Tip: If you need to solder fittings, we recommend professional installation. In lieu of sweat connections, you can opt for water heater supply cables. These options may include compression fittings or push-to-connect fittings.

Connect the Gas Supply

Next, attach the water heater components that connect to the gas supply line.

• Clean all threads before connecting the gas line with a wire brush or rag.
• As you connect the black pipes, apply a gas-rated thread seal or piping compound. There are kits that can be used to install gas water heaters if you don’t know how to connect black iron pipes. Follow the instructions provided by the manufacturer if you are using a kit.
• Two pipe wrenches are required to assemble and tighten each fitting.
• The union fitting should be installed last, as it connects to the existing line. Gas-rated pipe joint compound should be applied to the flare connection of the union.
• Turn on the water supply. To fill the tank with water, open the water valve. To drain air from the system, turn on one or more hot-water faucets.

Tip: Attach seismic straps to hold the water heater in its place if required by code This prevents earthquake damage.

Check the Gas Line for Leaks

Before you go, make sure to check the gas line for any leaks.

• Open the gas supply valve as the tank fills. Use a gas leak detection product to check for leaks. A sponge or spray bottle can be filled with a mixture of liquid dish soap, water, and water.
• Then, apply the solution to the new fittings. Look out for bubbles.
• All connections should be tested. You will need to tighten the connection or refit it if there is a leak. Turn on the Control Knob and light the Pilot

New water heaters come with an ignition switch that lights the pilot. For more information, refer to the owner’s guide. These steps will help you if your unit does not have an ignition switch.

• Take out the burner access panel.
• To adjust the pilot position, turn the knob at the top of the control box.
• To the pilot access opening, hold a barbecue lighter or a match in the fireplace.
• After the pilot starts to ignite, press and hold the reset button on your control box for 60 seconds.
• The knob at the top of the control box should be turned to the “on” position. The burner should start to ignite.
• If it does not, take out the access panel and relight your pilot.
• Replace the burner access panel, and adjust the temperature control to a temperature of 118 to 123 degrees.

Check that your gas water heater vents properly. Turn off the hot water faucet and close all windows and doors. Wait one minute until you hear the gas burner of the water heater ignite. Then, move a match close to the draft hood. The fumes may not be venting properly if the smoke does not draw up the vent pipe. If this happens, immediately open all doors and windows to allow a professional to inspect the venting.

It can be difficult to learn how to install a tank water heater. If you are not familiar with working with natural gas, soldering and complying with local installation codes, don’t attempt to install a gas water heater by yourself. Our gas water heater installation services include the removal of your old heater.