How to Install Hot Water Heater Expansion Tank

When you heat water, it expands, and since it is not compressible, the pressure in the pipes increases if there is no more room. To deal with the thermal expansion of water, you install the extension tank to the water supply pipe to prevent water pressure from getting too high. The implication of too much pressure in the conduit pipes is the severe damage to joints, fixtures, valves as well as the water heater and so the expansion tank acts as a safety device.

There are many ways of installing an extension tank, but as your plumber will tell you, it is to use a galvanized pipe. You can fit on either the hot or the cold water pipes; however, it does not matter the proximity to the water heater. Installing an expansion tank is a job you can handle armed with this guide and the right tools.

What You Need

To successful install an expansion tank, you will need the following items.

• Water heater expansion tank
• Pipe wrench
• Hacksaw
• Drill
• Hand pipe threader
• Teflon tape
• Pipe joint compound
• Screws
• Tee fitting

Install Your Expansion Tank

• The capacity of your water heater will dictate the size of the expansion tank. The attendant at your local hardware store can help you in purchasing the tank, given that you know your water heaters capacity. While you are at the store, you can buy the tools stated above.
• Cut the supply of water to your water furnace. Shut off the water at the primary supply line to the house or if you have a shut off valve on your supply line, close it.
• If your water heater uses electricity, turn off the circuit breaker that supplies electricity to the water heater or cut the gas supply to the heater.
• Identify the horizontal cold water pipe and position the expansion tank on the supply pipe. Mark and drill on the wall where the mounting brackets will go.
• Cut the inlet pipe and prepare threads on the two ends. Install the tee fitting using the pipe wrench and ensure to use the pipe joint compound and Teflon tape to avoid any leaks after installing the tank.
• Lastly connect the expansion tank to the tee fitting. Wrap Teflon tape and apply pipe joint compound to both ends of the connecting pipe and ensure the joint on the tee fitting and the expansion tank is tight enough.

Open the cold water supply and if there are no leaks, turn on the power or gas supply and check the expansion. If you get hot water from your taps, then you have successfully installed the water pipe.

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