Water leaking at night...The expansion tank explained!

The Importance of Expansion Tanks in Home Plumbing

As water heats up in a water heater, it naturally expands, a process known as thermal expansion. This expansion increases the volume of water, leading to excess pressure within the water heater's tank.

Modern plumbing systems are equipped with check valves that prevent water from flowing back into the public supply, reducing the risk of contamination. While this ensures the safety of your water supply, it also traps the expanding water within your home's plumbing system. Without a way to relieve this increased pressure, it can wreak havoc, leading to a significant increase in the likelihood of leaking faucets.

What is a Water Heater Expansion Tank?

A water heater expansion tank, also known as a thermal expansion tank, is a small, secondary tank that attaches to the water supply pipe leading to the water heater. Its primary function is to absorb the extra volume created when water heats up and expands. By providing this additional space, it prevents dangerous pressure from building up in your water heater and plumbing system.

How Does It Work?

The expansion tank is divided into two chambers: one filled with air and the other meant to hold water. As the water in the heater expands, it flows into the tank, compressing the air in the other chamber. This compression effectively relieves the pressure within the closed water system. By regulating pressure in this way, the tank protects vulnerable components like:

• Valves in plumbing fixtures
• Joints in supply pipes
• Seals and gaskets within the water heater itself

Without this pressure relief, these components are subjected to constant stress, significantly increasing the risk of leaks.

Why Leaking Faucets are a Common Sign

One of the most common signs of insufficient pressure relief is an increase in leaking faucets. As the pressure within the system rises, it forces water past the seals and gaskets within faucets, leading to drips and even more significant leaks over time.

Why Some Homes Don’t Have Expansion Tanks

Many older homes may not have an expansion tank, as they were not always a standard requirement. However, in modern homes with closed water systems, the absence of an expansion tank can lead to a significant increase in the risk of leaking faucets and other plumbing problems.

Potential Risks Without an Expansion Tank

If your home doesn't have an expansion tank, you could experience:

• Increased Leaking Faucets: This is the most common and noticeable symptom, as the constant pressure puts strain on the seals within faucets.
• Rapidly Deteriorating Washers: The increased pressure can accelerate the wear and tear on faucet washers, leading to frequent replacements.
• Increased Water Hammer: Sudden pressure surges can occur, causing banging sounds in the pipes and potentially damaging the system.

When to Consider Adding an Expansion Tank

• New Water Heater Installations: If you are installing a new water heater, check your local building codes. Many municipalities now require expansion tanks.
• Pressure Relief Valve Dripping: Constant dripping from the pressure relief valve is a strong indicator that you need an expansion tank.
• Frequent Plumbing Repairs: If you are experiencing frequent repairs to plumbing fixtures or pipes, an expansion tank can help prevent future issues.

By installing an expansion tank, you can significantly reduce the risk of leaking faucets and other plumbing problems, ensuring a more reliable and longer-lasting plumbing system.

*This is a recommendation only. Talk to a professional to make sure this is suitable in your situation*