How to Replace a Natural Gas Water Heater

A water heater
  • 3-5 hours
  • Intermediate
  • 800-1,500
What You'll Need
Screwdriver
Wrench
Powered saw
New gas water heater
Copper piping
Threaded couplers
Solder
Gloves
Eyewear
Solder torch
What You'll Need
Screwdriver
Wrench
Powered saw
New gas water heater
Copper piping
Threaded couplers
Solder
Gloves
Eyewear
Solder torch

Among residential water heaters, a natural gas water heater is often the preferred choice. Despite being durable performers, water heaters often need replacement after years of sustained usage. Replacing your natural gas water heater can be easier if you use the following information.

Step 1 - Procure New Natural Gas Water Heater

When buying your new natural gas water heater, ensure that you pay special attention to the size of water tank that defines its water-supply capacity. Other considerations include warranty periods and anti-corrosion treatment. Select a natural gas water heater that is compatible with the existing venting system. Water heaters with direct vents are the most preferred option.

Step 2 - Disengage Old Natural Gas Water Heater

Prepare yourself with plastic gloves and protective eyewear. The site of installation needs to be prepared by removing the old natural gas water heater. Remove any insulating material that is wrapped around the tank of the heater. Shut-off the main water supply line. To ensure that there is no residue water within the plumbing system, open all taps and drain-out the last drops of water. You can attach a garden hose to the main spigot of the tank to ensure that any trace of water is slowly drained-away as you proceed with your project. Turn off the gas valves of the tank. Wait for the indicator to show that there is no more gas in the heater’s circulating system.

Step 3 - Remove Old Natural Gas Water Heater

You need to disengage the plumbing lines of the tank. The water supply lines can be easily dissembled with a wrench. Some tanks have copper piping. You have to saw-off the piping with an electric saw. Remove the gas line of the natural gas water heater. These are usually located along the bottom of the tank. Similarly, unfasten the tank’s flue. Use a screwdriver to unfasten screws holding the flue. Ask someone to help you in lifting the old water heater and placing it away from the installation site.

Step 4 - Start Assembling of New Natural Gas Water Heater

Move the new natural gas water heater to the installation site. Start by connecting the vent pipes. This pipe has a dedicated opening along the top-end of the heater.

Step 5 - Connect Water & Gas Supply Lines

Water heaters with flexible water supply lines are the easiest to connect. You can simply tighten their screws with a wrench. The copper piping connection is more demanding. You need to solder the new copper piping. You need a thread coupler for this and a solder torch. The coupler is attached to end of the piping. Use a solder torch and solder material to heat and fuse the pipe with the new tank. This is often referred to as sweating the coupler with the tank’s body. You need to do this for the hot and the cold water-supply line. The gas line is easy-to-secure since it has a dedicated input valve and standard screws that can be tightened with a screwdriver.

Step 6 - Check Newly Installed Natural Gas Water Heater

To check the installed water heater, turn-on the gas-supply valve and light the pilot. Adjust the thermostat to the required temperature and wait for a few minutes. Open the faucet connected to the hot water supply line to assess if the newly installed water heater is properly heating the water.