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What is an Expansion Tank

Home Interior With Boiler System In Basement

Have you ever wondered, what is an expansion tank? In the world of plumbing, there are numerous components and systems that work together to ensure safe and efficient water flow. While most people are familiar with components such as pipes, faucets, and fixtures, there are many more components that play a critical role behind the scenes. One of these is the expansion tank. Keep reading to learn about what is an expansion tank, the basic components, how they work, different types, and more! 

Breaking Down the Basics

While expansion tanks are essential, they are often overlooked. These tanks serve a specific purpose, primarily in closed-loop plumbing systems where water is heated. These systems include residential and commercial boilers, water heaters, hydronic heating systems, and more. The main function of the expansion tank is to accommodate the expansion and contraction of water as it heats and cools within the system to ensure the water pressure is safe and efficient. 

Do I Need an Expansion Tank? 

Water expands when it’s heated and contracts when it’s cool, which is why expansion tanks are so beneficial. These changes can lead to fluctuations in water pressure, and without an expansion tank, the pressure can spike, causing damage to pipes, fixtures, and appliances creating a headache and a financial burden for your home or business. Conversely, as water cools, it contracts, which can potentially create a vacuum effect that can lead to damage or the collapse of pipes. To ensure your pipes and other plumbing fixtures remain efficient and undamaged, it’s best to install an expansion tank. 

How Expansion Tanks Work

An expansion tank comprises a sealed chamber divided into two sections by a flexible diaphragm or bladder. One side of the expansion tank is connected to the plumbing system, while the other side is filled with air or gas, typically nitrogen. As the water in the plumbing system heats and expands, it flows into the expansion tank, compressing the gas or air in the chamber. This action allows the expansion tank to absorb the volume without the pressure spike noted above. Additionally, during the cooler stage, the diaphragm or bladder pushes the stored air or gas back into the system to maintain a consistent pressure level. 

What is an Expansion Tank Type? 

There are two main types of expansion tanks that are frequently used, diaphragm and bladder expansion tanks. Keep reading to learn more. 

Diaphragm Expansion Tanks

These tanks feature a flexible diaphragm that separates the water from the air or gas chamber. Diaphragm expansion tanks are known for their durability and reliability, making them popular for residential homes and commercial properties. 

Bladder Expansion Tanks

Bladder expansion tanks use a rubber bladder to separate water, gas, or air. These tanks offer precise control over the pre-charge pressure, making them suitable for systems with specific pressure requirements. 

Expansion Tank Sizing and Installation

Proper sizing and installing an expansion tank are crucial to the system’s effectiveness. Expansion tanks come in various sizes to accommodate different plumbing systems. To determine the appropriate size for your system, you need to consider total system volume, temperature changes, and maximum allowable pressure. It’s best to consult a professional like the team at Goodbee Plumbing to ensure you are selecting the right expansion tank. 

Installation of an expansion tank involves connecting it to the plumbing system near the water heater or boiler. The expansion tank should be positioned where it can efficiently absorb the expanding water without causing any obstructions or delays to the other plumbing system components. Additionally, it’s essential to ensure you follow guidelines and plumbing codes during installation. Our team is well-versed in all plumbing codes and will gladly help set up your expansion tank without draining your wallet! 

Expansion Tank Benefits

Expansion tanks offer several essentials in plumbing systems, including but not limited to: 

  • Preventing Pressure Buildup: An expansion tank’s primary function is to prevent excess water buildup, which prevents potential damage to pipes, fixtures, and appliances. 
  • Enhancing System Lifespan: By reducing the stress on plumbing components caused by pressure fluctuations, expansion tanks can extend your system’s overall lifespan.  
  • Ensuring Energy Efficiency: Maintaining a consistent water pressure helps systems like the boiler and water heater operate efficiently, leading to potential energy (and financial) savings in the long run. 
  • Reducing Water Hammer: Expansion tanks help minimize water hammer, a phenomenon characterized by loud, banging noises when water flow suddenly stops or changes direction. 
  • Protecting Against Leaks: Expansion tanks also help prevent pipe and fixture leaks when pressure surges. 

Expansion Tank Issues and Maintenance

Now that we’ve answered the question of what is an expansion tank and reviewed its importance and benefits, we can discuss some common issues and proper maintenance. While expansion tanks are relatively low-maintenance, they may encounter some issues over time, which most commonly consist of: 

  • Waterlogged Tanks: Over time, the air or gas in an expansion tank can be absorbed by the water, causing waterlogged tanks. This diminishes its ability to absorb expanding water. If your expansion tank becomes waterlogged, you most likely will need a replacement tank. 
  • Pressure Problems: If the expansion tank’s pre-charge pressure is not set correctly or if it loses pressure over time, it can lead to pressure problems. While this does not always mean you need a replacement tank, contacting a professional is best. 
  • Leaks: Leaks can occur in the diaphragm or bladder; if this happens, you will need to replace your expansion tank. 

Routine maintenance involves checking the pre-charge pressure and inspecting for any leaks. If any issues are detected, or your system is not operating as efficiently as before, be sure to address them as soon as possible. Contacting a professional like the plumbers at Goodbee is an excellent idea because our team will not only fix your problem but can answer any questions from what is an expansion tank to technical questions, highlighting their industry knowledge. 

Depend on Goodbee Plumbing to Answer What is an Expansion Tank and More

Expansion tanks are the unsung heroes that play a vital role in closed-loop plumbing systems. By accommodating the expansion and contraction of water, expansion tanks prevent potential damage to your plumbing system. The team at Goodbee Plumbing can help you along this process by further explaining what is an expansion tank, the benefits and drawbacks of expansion tanks, as well as your installation and repair. Contact us today to schedule your appointment!

You can also read our blog to find answers to many other plumbing questions, as well as DIY tips and tricks. 

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