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Houston Water Heater Installation: Expansion Tanks

Water Heater

During Houston water heater installation, you might notice your plumber install a smaller tank on top of your water heater. Or, maybe you’ve noticed it on your existing water heater as you consider replacement. This is an expansion tank, which can play an important role in preserving your water heater and plumbing system. Water heater expansion tanks typically look like a small propane tank connected to your water heater by a piece of pipe. So, do you need an expansion tank? What is their purpose? We’ll cover this and more in this article. 

Do I Need an Expansion Tank for Houston Water Heater Installation?

Do you need an expansion tank for your new water heater? Not every home needs a water heater expansion tank, so you should talk to your Houston plumbing company about the particulars of your plumbing system. 

Generally speaking, if you have a check valve or pressure regulating valve installed on the supply line leading to the water heater, then it may be a good idea to install an expansion tank during Houston water heater installation. This can help prevent extra wear and tear on your plumbing system and fixtures. 

What is a Water Heater Expansion Tank?

So, what is a water heater expansion tank, anyway? This is essentially a device that helps protect your plumbing system from extreme water pressure. As you heat water, it tends to expand. Generally, 50 gallons of water expands to 52 gallons of water as you heat it up. Therefore, as your water heater heats the water in the tank, the water expands. With nowhere for it to go, that extra water presses against the tank, pipes, and other pieces of the plumbing system. This can increase water pressure throughout your home’s plumbing system, which can lead to early wear and tear or damage for things like your water heater tank, pipes, and plumbing valves. 

An expansion tank helps prevent these issues. Expansion tanks are plumbing devices that give extra water somewhere else to go to prevent high water pressure in your home. Basically, as the water expands, it enters the expansion tank rather than pressing against the plumbing. It achieves this by using a special rubber diaphragm that separates the tank into a top and bottom area. One half has compressed air and the other fills with water as needed. 

Ask Your Plumbing Company if Your System Needs an Expansion Tank During Houston Water Heater Installation

As we mentioned earlier, not every home needs an expansion tank for their water heater. It depends on the particulars of your plumbing system, which is why we recommend asking our plumbers for recommendations based on your home. 

However, most homes can benefit from installing an expansion tank during Houston water heater installation. That’s because most residential plumbing systems are a closed loop. To understand what this means, let’s break down the differences between an open and closed plumbing system. 

An open plumbing system essentially allows water to flow in and out of the system freely. Therefore, as water expands from the water heater tank, it simply flows backward through the water supply pipe and, in theory, can flow all the way back to the municipal lines, though the average water heater doesn’t hold enough water or heat to cause that much water expansion.

By contrast, closed systems don’t allow water to flow back toward the city lines. Instead, there is typically a valve that prevents backflow in the event of water expansion. This creates a closed loop that traps the water where it is once it passes through the valve. In these cases, that’s where an expansion tank helps.

It’s also important to note that pressure issues from water expansion only applies for tank-style water heaters. Because tankless units don’t store water, they avoid many of these issues and therefore don’t need an expansion tank. So, if you choose tankless water heater installation in Houston, then you won’t need an expansion tank. 

Our plumbers can help you determine what type of plumbing system you have and whether adding an expansion tank during Houston water heater installation can help prevent damage to your plumbing system. 

Choosing the Right Expansion Tank For Houston Water Heater Installation

If you need an expansion tank for Houston water heater installation, then you might wonder what kind you need. Once again, it’s best to talk to our plumber about different options and which will be best for your home. However, here’s some general information that may be helpful to know. 

The biggest difference between expansion tanks is the size you need. Most residential options come in either 2-gallon or 4.5-gallon options. However, you can get larger as needed. To choose the right size, our Houston plumbing company assesses the size of the water heater tank as well as the water pressure from the supply line to the water heater. 

Most residential water heaters hold between 40 and 50 gallons of water, and normal water pressure is between 40 and 60 psi. In these ideal circumstances, you should only need a 2-gallon expansion tank for Houston water heater installation. However, if you have a larger water heater or higher pressures, we may recommend a larger expansion tank. 

Replacing the Expansion Tank

Another important thing for homeowners to know is that expansion tanks typically have pretty short lifespans. On average, they last between 5 and 10 years, so they might need replacement before your water heater does. Our plumbers can check the expansion tank to ensure it’s working properly and replace it as needed during your annual water heater service appointment. 

However, there are a few things you can do to “test” the expansion tank for your water heater. The first is to feel the outside of the tank. The half that holds the extra water should feel warm, while the other half which holds the air should feel cool or room temperature. If the entire tank feels warm, that’s usually a sign that the entire tank is full of water and that the rubber diaphragm has broken. This means it’s time to replace the expansion tank. 

Another thing you can do is tap the outside of the tank and listen to the noise it makes. If the expansion tank diaphragm is intact, then the side that holds air should sound hollow and make a slight pinging or ringing noise. However, if the entire tank makes a lower, duller sound, it may be full of water and no longer working. In this case, call our team of plumbers for help with a replacement. 

Water Heater Solutions from Santhoff – Your Houston Plumbing Company

Need water heater installation, repair, or maintenance? Call our experts at Santhoff Plumbing! We are a trusted plumbing company serving the Greater Houston area and offer a wide range of services, from Houston water heater installation to emergency repairs for burst pipes. Our plumbers offer years of experience and friendly service to help you take care of your home’s plumbing system. Contact us today to schedule service or call our 24-hour line at (713) 360-2185 for help with plumbing emergencies. 

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