Can I replace my expansion tank myself?

Author: Jackson Howe  |  Last update: Thursday, January 1, 2026

It is possible to replace the expansion tank yourself, but it is recommended that you hire a professional plumber to do the job. Replacing the tank involves draining the heating system and removing the old tank. The new tank must then be installed and the system refilled and repressurized.

Can you replace your own expansion tank?

You could change it easily enough on your own, but unless you know how to bleed your system you might as well have the plumber change it while he's there. Good or not, they don't really last forever.

How long does it take to replace an expansion tank?

However, on average, an expansion tank can last 5 to 10 years or even longer if properly maintained and inspected regularly. It is recommended to check the expansion tank for signs of damage or wear, such as leaks or rust, at least once a year and replace it if necessary.

Do you have to drain a water heater to replace an expansion tank?

Whether you're adding a new expansion tank to an existing water heater or you are replacing a water expansion tank, you will need to drain your water heater. Various pipe connections have to be made and you don't want water to end up all over the floor, so drain the water heater before your work begins.

How much does a plumber charge to install an expansion tank?

According to Forbes, the average cost of expansion tank installation is $220 (CAD 270) for materials and labor, with most homeowners spending between $90 and $350 (CAD 122 and CAD 473). Expect to spend between $40 and $200 (CAD 54 and CAD 270) for the tank itself, excluding the cost of labor.

What Is This Tank? How to Replace and Maintain a Water Heater Thermal Expansion Tank

What is the life expectancy of an expansion tank?

But expansion tanks can wear out. The average life of your tank can be anywhere between five and 10 years. You can extend the life of your expansion tank by making sure that your home's water pressure matches the air pressure in your expansion tank.

How much does it cost to replace a well expansion tank?

Replacing a well pressure tank costs $500 on average, but it can cost between $300 and $700, depending on the tank's size, capacity, and labor costs for professional installation.

How do I know if my expansion tank is bad?

How To Check If Expansion Tank Is Bad
  1. The relief valve drips during the water heater recovery period, despite no water usage.
  2. The water heater tanks in your home fail prematurely.
  3. You will hear a metal cracking noise stemming from your water heater when pressure is relieved.

Can I change an expansion vessel myself?

Generally, the pressure on your central heating system will be 1.5 to 2 bar. When it is lower than 1.5 bar, it is very likely that the expansion vessel is broken. Replacing an expansion vessel is very simple. You can easily do it yourself, and thereby save the cost of calling in a fitter.

Do I really need an expansion tank on my water heater?

An expansion tank is required on the supply line coming into the tank to reduce the tank stress which will shorten the tank's useful life. An alternative to the expansion tank is an approved pressure relief valve assembly. These devices are required on closed systems, which is public water.

How much is a new expansion tank?

A water heater expansion tank costs $150 to $450 on average, with a national average of $325. The total cost depends on the size and type of tank. A water heater expansion tank costs an average of $325 to install, and most people pay between $150 and $450 for the task.

What happens if you don't install an expansion tank?

As plumbers know, the expansion tank equalizes pressure throughout the plumbing system by providing a space for hot water to flow into. Without an expansion tank, pressure would be distributed to the entire plumbing system, straining it and decreasing its lifespan.

How often should I drain my expansion tank?

Water will get inside of the system, of course, which means that you are going to need to drain expansion tank to make sure that the pressure that the tank absorbs is always at an optimum. This task shouldn't take very long, and should be done a couple of times a year by you or a professional.

How do I know when my expansion tank needs to be replaced?

Signs It's Time to Replace an Expansion Tank

If the tank is no longer effectively maintaining or controlling this pressure, it indicates a malfunction. Loss of pressure control could mean that the internal air bladder or diaphragm has ruptured, or that the tank has lost its pre-charge.

Who fixes expansion tanks?

You must call a plumber immediately if you notice any water leaking from your expansion tank. They will evaluate the issue and ensure it is properly repaired or replaced before further damage occurs.

Is it code to have an expansion tank?

Expansion tanks are required by code in all new water heater installations in closed systems. A closed water system uses check valves, backflow prevention devices, pressure-reducing valves, or other devices on the supply line to prevent water from being sucked back into the municipal water supply.

What is the rule of thumb for expansion vessels?

The 'rule of thumb' calculation is that the pressure vessel size is equal to 6 seconds of maximum flow. For example: if the design maximum flow rate of a booster set is 3 l/s – the required vessel size would be 18 litres.

What are the symptoms of a failing expansion vessel?

Firstly, you may observe fluctuating pressure levels within the system, which can manifest as inconsistent water flow in taps or heating systems. Another sign is the frequent activation of the safety pressure relief valve, indicating that the vessel isn't maintaining proper pressure.

How much does it cost to change an expansion vessel?

One chamber contains nitrogen or another inert gas, and the other contains water from the elsewhere in the heating system. Replacing a boiler expansion vessel can incur a range of costs, from £25 at the low end to more than £100 at the high end. The exact price will vary depending on the brand and make of the boiler.

Can an expansion tank be repaired?

Sooner or later, you may notice some signs that your expansion tank requires repair. Hot water heaters can be complicated, and it's usually best to enlist a trained plumber to make the repairs for you.

Can you drive with a leaking expansion tank?

Check your dipstick and the engine oil cap for coolant and whether there's white smoke coming out of the exhaust, if there are the coolant is leaking into the engine and you should absolutely not drive the car in that state.

Why do I suddenly need an expansion tank?

When extra pressure builds up in the hot water system, it could cause pipes to burst, resulting in costly repairs and even greater risks if someone gets hurt. With an expansion tank installed, excess pressure is diverted away from pipes and other components which can help prevent accidents and damage.

What is the life expectancy of a well expansion tank?

Average Lifespan

The typical lifespan of well pressure tanks is 10 to 15 years, though this can vary depending on the tank's quality and maintenance. Higher-quality tanks can last 5 to 30 years, with the average being around 15 years.

Is it hard to replace a well pressure tank?

If your new pressure tank is exactly the same as your old one, replacing it will be a breeze. Position it in the same spot as your old tank and thread the inlet pipes, outlet pipes, and the water line into place, tightening them with a pipe wrench.

What happens when expansion tank goes bad?

Without an expansion tank to accommodate this expanded water volume, the pressure within the system gradually builds up until something gives way. Typically, the water heater is the first to suffer, but pipes, fittings, and other water system components can also break.

Previous article
What's the difference between enameled and cast iron?
Next article
Which refrigerator is best LG or Whirlpool?