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Water Heater Expansion Tanks: What are They and Do I Need One?

Water Heater Expansion Tank

If you are suffering from any type of thermal expansion in your home, then the best option is to get the help of a water heater expansion tank. Plumbing difficulties may happen at any time and any date. The risk of pressure damage along with your tankless water heater is very common. This may also expand the risks of the plumbing configuration.

So taking the help of a thermal expansion tank water heater means that you can get added benefits. So if you have a 50-gallon heater, it will become almost 55 gallons with the help of thermal expansion. So adding a proper expansion tank can be ideal for you. If you are considering such, here is a complete guide that you can follow.

Why Do I Need an Expansion Tank for Water Heater?

Overflows from your heater may be highly risky for anyone. At times, there may be severe plumbing issues or any mechanical fault that may lead to the expansion of the hot water. But if you do not have an expansion tank, the hot water leas may damage the entire a lot of heaters available in your home that do not have any expansion tank.

So, if the heater faces any type of thermal expansion in this situation, the overflowing of hot water may be a common issue. As a result of this, hot water flowing out from the heater may cause serious injuries to your body. Because of this, the Temperature and Pressure valve is already damaged and the heater is now out of control.

To avoid such situations, you must opt for a proper expansion tank that will be saving you from accidents. With the help of such a water expansion tank, the overloaded water will start to get stored in it and thus, it will not flow out of the heater. As a result of this, there will be no further leaks present from the expansion tanks.

Without installing a proper expansion tank with the product, it becomes difficult to control the leakage and if the heater starts to overflow, it may damage the internal components. At the same time, it also reduces the lifespan of the heater. So having a water heater expansion tank with the product will always help you to get the best result.

How do Thermal Expansion Tanks Work?

Just imagine a situation when you are using a pressure cooker to boil the water. What happens next after you keep it on for hours? Yes, it blows up the whistle and releases the pressure inside. The water present inside does not heat up easily and it starts to release the steam. If you come with a clear view of the situation, the water inside expands when it is heated up. The same happens with your water heater tank. 

In the case of a pressure cooker, there is no PRV installed in the line to contain the water pressure. So it bursts out. Not only this, but the heater also comes with a temperature and pressure valve. This valve works exceptionally well to restrict the water pressure from the municipality lines. In such cases, the pressure is directed back towards the input lines and can bother the entire system.

If you have a separate Pressure regulating valve installed on the line, it will help you a lot to contain the excess pressure trapped onto the piping system of your home. However, because the costs for changing the entire plumbing system seems to be high, many people may not even want to get it. 

This is where the expansion tank comes in to complete the work. If you install the tank properly, it will help you to absorb the excess pressure that is present on the pipe. In our home, almost half of the tank is filled from the main water system that is connected to the home. However, the other half is present with compressed air. Between the two layers, there is a butyl rubber bladder present along with the product. As a result of this, the heater tends to be hotter and it may easily expand. This allows compressing the air and then heat the water on the other side.

When is it required?

When it comes to a closed-loop system, the use of an expansion tank means that you can get control over the water pressure. In the case of the closed-loop system, the water pressure becomes gradually higher and it turns out to be much higher than any regular closed system.

So practically, when the water pressure is higher than 80 PSI, you will always require an external pressure release valve to keep this under control. It is mainly because the constant high pressure inside the heater may reduce the life expectancy. The external tank comes to great help when you meet such situations as it meets the work rate of the P&R Valve.

The thermal expansion works by the fluctuation of high pressure because of the closed-loop system. A lot of factors will be important for you when it comes to the expansion tank. However, the main component is all about the pressure being released and what you need to control.

Finding the Right Water Heater Expansion Tank

There are a lot of factors that you need to consider when you buy an extension tank. Installing that tank is not the only factor that you need to consider. You need to pick the right size, check for the components and make sure that everything is perfect. So you must explore multiple products available in the market today before you opt for a proper water heater tank. Follow this buying guide below to know more.

How to Properly Size an Expansion Tank?

When it comes to picking up the right size, you need to consider a few factors in your mind. Some of them are mentioned below:

1. Water Heater Capacity –¬†Now this depends on how much the capacity of the heater is and how it can provide you with a proper quantity of hot water.

2. Household Water Pressure –¬†The next thing that you need to consider is the water pressure that is involved. You can take the help of a gauge and then measure the PSI available from a hose or faucet in your home. However, another option is to contact the water company.

So before you move on to select the right size available. For installing an expansion tank, you need to keep in mind that the water pressure must be within 50-60 PSI. If the pressure is more than 80 PSI in your home, you need to take the help of a pressure reducing valve.

What Happens if I Pick Up a Wrong Size?

If you pick up the wrong size while opting for the tank, pray that the error is conducted on the larger size and not the smaller. This is mainly because choosing the right size of the expansion tank is more important than anything else.

If the expansion tank is way too large than the requirement, you may not have to worry too much. Yes, you may face some problems to install the product, but it will be safely able to handle the extra flow of water.

At the same time, if the expansion tank is too small than that of the system, even the T&P release valve will be of no help. The overflow will always continue and eventually, it will end up wasting the money.

How to Install an Expansion Tank?

Installing the expansion tank is not the most difficult thing that you need to consider. However, if you pick out the right size of the product, it will not be a difficult thing.

But before you start to install the product, you must keep in mind the precautions. Check for the available water pressure using a gauge and then install a pressure reducing valve to the heater. You can now follow the steps below to know more.

1. The first thing that you need to do is to completely disconnect the water and the power supply. While you are working with the product no switches and faucets are turned on by default.

2. The next thing to do is to bring out the expansion tank and then the accessories present with the product. You can check for the size and then you can have a hold of the tape and the tee fitting. They are of great help.

3. Now when you are ready to install, you need to confirm the supply line of the cold water. Check for both the input pipes and the output faucet. If you are getting confused, just mark them out.

4. You need to carefully place the expansion tank on the line that supplies cool water. Mark a spot on the wall where you will be installing the mounting pipes. This will help you to attach the tank to the supply line.

5. The next thing is to attach the heater tank with the expansion tank. If you are done with this, simply wrap up the spot with a plumber’s tape. So you can easily secure the connection with a wrench. 

6. Check if there are any loose fittings on the pipe or any leakage present. Once you are clear, you need to restore the water supply to the heater. This will help you to get the proper result available.

7. Now you can wait for the heater to perform. If there is still an overflow from the heater, there may be some problem while installing. If there is no overflow, you can now start using the expansion tank easily.

How to Maintain a Hot Water Heater Expansion Tank?

In any device you purchase, putting in a proper maintenance check is always important. Most of the experts recommend that you must take the help of a professional before putting a hand on any electric device. 

Why is Maintenance needed for an Expansion Tank?

Maintenance is highly important when it comes to using the product. The expansion tank is specifically designed with an internal bladder.

This bladder performs the role of separation of water and air inside the tank Because of any leaks from the heater tank, the bladder will perform “diffusion” and it can be working at a rate of 1 PSI a year.

Apart from this, there is also an internal bladder. If the internal bladder is damaged, the tank will not be able to drain properly. So it is also important to keep maintenance. With proper maintenance, the expansion tank can easily last for 6 years.

A. Checking the Bladder

1. Turn off the supply of water and then you can easily relieve the pressure with the help of the faucet.

2. Once you are done with this, just remove the cap and then reach out to the valve system. If you attach the tire pressure gauge, it should be around75 psi.

3. If the air pressure is low, the expansion tank has failed and you need to replace it immediately.

4. If you find any air pressure inside the tank, you will now have to check for the water pressure available.

5. Once you are done with the measurement, you need to check for the bladder. A quick way to get this done will be to press the Schrader valve that is located outside the tank.

B. Checking the PSI

Another thing that you need to make sure is to check for the PSI. But you can only attain this once you are done with the bladder check. The owner’s manual will be provided with the correct psi for the tank. So you can take the help of the pressure gauge to know if the psi is still the same or there is a massive difference.

Final Talk

Having a thermal expansion tank can give you a lot of advantages over the basic plumbing problems. But for this, you need to understand that the expansion tanks need to be installed properly.

Maintenance is another key factor that you need to consider while you are about to use such tanks. Keep in mind that the better you will maintain the products, the better it can provide you with durable and stable work.

However, if you have some more doubts about choosing a proper water heater expansion tank, you can always drop down your comments below. Do follow the entire guide above to know about how they work installation maintenance and much more.