Expansion Tank

Find out if your water heater requires an expansion tank and how they work. Receive expert installation from Legacy Plumbing in Frisco, Plano and DFW.

What is an expansion tank and do I need one? Why is it required in some cities of DFW? Why hire a plumber for expansion tank installation? Many of our customers have questions on this small appliance, find answers and learn why Legacy Plumbing is the best option.

What Is an Expansion Tank?

When water heats up, it expands. If your system has a closed-loop system, that expansion has nowhere to go. It just spikes the pressure in the system. A water heater expansion tank (also called a thermal expansion tank) relieves that pressure on your lines, fixtures, and even appliances. The expansion tank looks like a small propane tank installed above your water heater and is filled with water and compressed air. As heated water expands, the air further compresses and the excess water occupies that space. Learn more about how an expansion tank works in this blog article.
Closed-loop systems require expansion tanks, so check to see if your home has this type of system. Check valves or pressure regulating valves installed on water lines in such systems trap the additional water pressure caused by heat expansion inside your home. This stresses your system, which is why 2018 plumbing code requires water heater expansion tanks on all closed-loop systems.

Thermal Expansion Tank Requirements in North Dallas​

City-specific requirements are subject to change at any time. We recommend referring to the authority having jurisdiction for the latest information on when an expansion tank is required in your area.

While expansion tanks are typically only required on closed-loop systems, some cities require them on every new water heater installation. At Legacy Plumbing, we stay in contact with the cities’ building inspection departments and make sure that everything is done up to their standards so that the inspection process goes smoothly.

Not All Expansion Tanks Are Equal​

There are many different manufacturers that make expansion tanks, and there is a great variance in the quality of the materials and the manufacturing processes. There are also a lot of different ways to go about installing an expansion tank on the system. Because expansion tanks are often installed inside homes in or in the attic with the water heater, the risk of water damage if they fail is very high.

At Legacy, we are committed to using the best quality materials and installation practices in order to protect your home. We only use high-quality stainless steel parts and have chosen an expansion tank manufacturer that stands behind its product. We have also refined our standard for installing these tanks so that you can count on it being done right every time.

Legacy’s expansion tank service is…​

  • Expert
    Legacy’s plumbers are experienced, skilled, and licensed professionals who go through additional training before they can wear the Legacy uniform.
  • All-Encompassing
    Legacy offers our award-winning service for hot water expansion tank installation, replacement, and repair.
  • Available in Your Area
    We provide expert plumbing services in North Dallas, Collin, and Denton Counties.
  • On-Time
    You’ll never have to wait on a Legacy plumber. We’ll be there when we say we will, guaranteed.

Don’t settle for just any plumber. Get expert expansion tank service with Legacy.

Our Work is Our Word.

Expansion Tank
The technicians with Legacy Plumbing are friendly, courteous, and knowledge. I've had them out twice recently, with two separate issues. Johnny replaced a cartridge in the guest bathtub for hot water as well as good water flow. Steven and Hubert installed a new expansion tank on my hot water heater. At my request, they also checked all the bathroom faucets and found them to be in good working order. I will definitely be using Legacy Plumbing again. When you call for an appointment, they are able to give you a dollar amount for the service/repair. Great company as well as exceptional technicians.
Expansion Tank
Absolutely blown away by Legacy Plumbing’s professionalism, honesty, knowledge, customer service, and quality of work!! Our expansion tank was literally leaking water everywhere so the situation was dire. I did what I could to stop water and called Legacy as a new customer. Enoch was at my door within 30 minutes of the call and ready to assess and attack the problem. Thank you Clifton for your quick thinking and response time and Enoch for fixing problems with integrity!! Well done gentlemen! I highly recommend and trust Legacy Plumbing!
Chad Hortenstine