Expansion Tank

Have you experienced irregular fluctuations in water pressure or unexpected leakages within your plumbing system? One major reason for such issues is thermal expansion – the action of water heating up in a closed system which, in return, generates an increased level of pressure.

In the absence of a proper means to contain the pressure, pipes are at risk of leaking. Aggravating the situation is the potential for water heaters bursting.

So here is an expansion tank—it helps in managing water pressure when a significant volume is experienced during heating periods. The expansion tank, therefore, helps in the prevention of most plumbing issues.

In the subsequent parts of this guide, we will look into the mode of operation of expansion tanks, the necessity of expansion tanks, and guide you on how to choose one for your system.

A Definition of an Expansion Tank

An expansion tank is a secondary tank equipped with a water heating system belonging to both residential and commercial premises. It is mainly utilized in closed plumbing systems.

Primary Function

Its primary function is to control pressure changes experienced by water while it is being heated, also referred to as thermal expansion.

Water expands when it is heated. If there is no venting option available for the additional pressure that comes with the rise in temperature, overloading the system might become the norm. An expansion tank acts as a reservoir where excess water is stored, maintaining steady pressure to mitigate damage to valves, pipes, and water heaters.

An expansion tank is an integral piece in most modern water heating systems as they greatly improve safety, efficiency, and durability.

How Does an Expansion Tank Work?

An expansion tank consists of a rubber diaphragm slitting a tank into two sections:

• The water chamber: Directly linked to the water heater, this chamber receives the expanding water.
• The air chamber: This chamber absorbs excess pressure to reduce strain on the plumbing system.

Functionality

• In normal circumstances, excessive pressure buildup from water expansion raises tension within the pipes.
• However, in an expansion tank, the water enters the water chamber rather than heightening the pressure from within.
• If the expansion tank needs to release water, the air chamber will push the water into circulation to maintain balance.

Key Benefits of an Expansion Tank

1. Avoids Failures in the Plumbing System

Without an expansion tank, pipes experience continuous strain, leading to bursts, leaks, or damage to fittings and fixtures. An expansion tank mitigates these issues by keeping the pressure in check.

2. Increases the Life Span of Water Heater

The water heater endures strain from high pressure, which shortens its lifespan. An expansion tank helps in stress reduction, ensuring increased durability of the water heater.

3. Controls the Water Pressure

Erratic water pressure can reduce system performance. An expansion tank maintains consistent water pressure to allow for true functionality.

4. Saves on Water Usage

Without an expansion tank, excessive pressure could trigger the Temperature and Pressure Relief (T&P) valve, leading to water wastage. An expansion tank allows for better water containment.

5. Observes Plumbing Requirements

Many jurisdictions mandate expansion tanks in closed plumbing systems. Installing one helps in avoiding penalties.

How to Tell That You Require an Expansion Tank

Some signs indicating the need for an expansion tank include:

• Presence of pressure-reducing devices built into your closed plumbing system.
• Regular water pressure fluctuations or burst pipes.
• The T&P valve discharges water so frequently that it becomes a nuisance.

In these cases, the best solution is installing an expansion tank.

What Are the Factors That Determine the Right Expansion Tank to Use?

1. Size of Your Water Heater

The expansion tank’s size must be compatible with the water heater. Larger heaters require larger expansion tanks.

2. System Pressure

Using a pressure gauge, check your home’s water pressure. Most home systems run between 40-60 PSI. The expansion tank must be rated for this range.

3. Temperature Settings

Higher temperatures cause greater expansion. If your water heater is often set at high temperatures, a larger expansion tank is recommended.

4. Proper Placement

For optimal performance, the expansion tank should be installed on the cold-water supply pipe farthest from the water heater.

How to Install an Expansion Tank

While you can install it yourself with basic plumbing knowledge, professional assistance is recommended.

Tools Required:

• Pipe wrench
• Adjustable wrench
• Teflon tape
• Pressure gauge

Step-by-Step Installation Guide:

1. Shut Off the Water Supply – Turn off the main water valve.
2. Remove Some Water – Open a faucet to release system pressure.
3. Wrap Teflon Tape – Apply Teflon tape to threaded connections to prevent leaks.
4. Fix the Expansion Tank – Attach it to the cold-water pipe leading to the heater and tighten securely.
5. Modify the Pressure – Adjust the air pressure in the expansion tank to match the system’s pressure (40-60 PSI).
6. Switch Water Supply Back On – Slowly turn on the water and check for leaks.

Tip:

If unsure, hire a certified plumber to ensure proper and safe installation.

Expansion Tank Maintenance Tips

To ensure longevity and efficiency:

• Look for Leaks – Inspect the tank and connections regularly.
• Check the Diaphragm – Replace the tank if water has entered the air chamber.
• Test Air Pressure – Use a pressure gauge periodically.

Proper maintenance can extend the lifespan of an expansion tank to 5-10 years.

Conclusion: Expansion Tank Requirement

An expansion tank is a critical component of water heating systems. It ensures better pressure control, increased efficiency, and enhanced safety.

Acting as a safeguard against pipe bursts, leaks, and water wastage, expansion tanks are indispensable in closed systems. Consult a professional for correct installation and ensure compliance with plumbing codes.