How Much Does an Expansion Tank Cost?

Los Angeles’s local city code for building and safety requires an expansion tank on every new tankless water heater installation. But what does that mean for your wallet? We’ve got you covered when it comes to all things expansion tanks, including their cost.

For over 15 years, we’ve installed tankless water heaters in homes across the Los Angeles area. In that time, we’ve dialed in how much installing an expansion tank will run our customers.

While the answer to how much an expansion tank costs is straightforward, we’ll also walk you through the main factor that can increase your total investment. Finally, we’ll land on why expansion tanks are so important.

Let’s get started!

How Much Does an Expansion Tank Cost?

There are two main sizes of expansion tanks: two-gallon and five-gallon. Depending on which one you go with, you can expect a price tag of $75 or $100. This price doesn’t include installation, which is where the majority of the cost comes from.

What Affects Expansion Tank Cost?

Unlike other components of tankless water heaters, expansion tanks are relatively straightforward. There’s really only one expense to worry about, and that’s installation.

When you’re looking into installing an expansion tank, you can count on a price of between $500 and $800. This price also includes the expansion tank itself. Depending on the size of the tank you choose, the size and length of your pipes, the amount of copper pipe needed, shut-offs, and check valves, the price will fluctuate within that range.

Since expansion tanks don’t come with tankless water heaters by default, you can count on these additional costs. Some companies offer premium installation packages that include an expansion tank and water treatment.

Why Are Expansion Tanks Important?

You might think that expansion tanks can’t be that important if they’re not sold with the water heater itself. The opposite is true, though.

Expansion tanks prevent serious damage from occurring within your water heater and plumbing system. As your family uses hot water, your tankless water heater is constantly heating water. When you stop using that hot water, it leaves excess heat and pressure in your tankless water heater, causing thermal expansion.

To relieve that heat and pressure, the excess water and pressure enter the expansion tank. This prevents leaks and other types of damage caused by the stress thermal expansion puts on your pipes. This can save you hundreds in repair costs down the line.

Ready to Install an Expansion Tank?

We’ve touched on how much expansion tanks cost with and without installation and why they’re essential. By now, you’ve got a better idea of what to expect before heading into your first tankless water heater consultation. You’ll be able to navigate the installation process without getting lost or knocked off balance by surprise costs.

Monkey Wrench Plumbing, Heating, Air & Electric has installed plenty of expansion tanks across Los Angeles County, and while they may be a requirement from the state, expansion tanks also end up saving homeowners hundreds of dollars in unnecessary repairs. So, whether you’re looking to get your home up to code before an inspection or just want that additional peace of mind, we can lend a hand.

Call us at (818) 213-1773 or visit our tankless water heater page to book a consultation.

If you’re just starting out your research, it’s best to get familiar with what a tankless water heater costs. This will help give you a better understanding of what a complete installation will cost, whether it’s a base or premium job.