How to Remove Air from Solar Water Heater: A Step-by-Step Guide

Why is there a need to remove air?

To remove air from a solar water heater, you’ll need to use the bleeding valve located on the highest point of your solar heater system. Carefully open this valve until water starts to flow out consistently, showing that all air has been purged. Remember to close the valve after completing the process.

Solar water heaters are the cream of the crop in energy conservation, harnessing nature’s pure and abundant sunshine to provide us with hot water. However, just like any other mechanical device, these systems too may face occasional glitches. A vexing issue you might encounter is trapped air within the system. Want to learn how to remove air from solar water heater? Well, you’re in the right place!

When trapped air is in your solar water heater, it reduces the efficiency of the system by creating a barrier between the water and the heating elements, leading to colder showers and higher energy bills. Thus, removing this air is a necessary task for the longevity and efficiency of your solar investment.

Understanding the structure of the solar water heater

Understanding the structure of the solar water heater

To understand the process of how to remove air from your solar water heater, you must first understand its structure. A solar water heater mainly consists of solar collectors, a heat exchanger, a storage tank, and pumping and control systems.

The solar collector absorbs the sunlight and transfers it to the fluid within. This heated fluid is then transferred via a pump to the heat exchanger located in the system’s storage tank. The heat from the fluid is transferred to the water in the tank through the heat exchanger.

And if you’re wondering, “Where does the vent fit into all of this?”, here’s your explanation. The vent, typically located at the highest point of the system, is an escape route for the trapped air. When air is released or “bled” from this vent, hot water circulation improves, leading to better heater performance.

Steps to Remove Air from the Solar Water Heater

Well, now that we have a comprehensive understanding of the system’s structure let’s dive into the step-by-step guide of how to remove air from your solar water heater.

First things first, during the commissioning (starting-up) process of the solar water heater, run the pump at maximum speed. This ensures that the water is pushed vigorously through the piping system, breaking the “hold” or friction that the air bubbles might have on the pipes’ interior walls. This practice helps release and eliminate most of the trapped air within the system.

Once the commissioning process is complete, don’t forget to reduce the pump speed. Running the pump at maximum speed is good for initial air removal, but for regular operation, it’s best to keep it at a moderate speed to avoid early wear and tear.

How to Remove Air from Solar Water Heater Vent

How to Remove Air from Solar Water Heater Vent

Let’s now master the technique of removing air specifically from the heater vent.

To begin, identify the highest bleed valve in your system. Slowly open this valve until a mixture of water and air sputters out. You’ll know it’s time to close this valve when the water flows out without any sputtering, indicating that all the air has been purged. Alright, task accomplished!

Maintenance Tips Post the Removal of Air

After learning how to remove air from the solar water heater, let’s turn towards its maintenance. You see, preventive maintenance is always better than a cure, especially when ‘cure’ could mean a time consuming, costly repair.

Keep an eye on the performance of your solar water heater. If you notice an abrupt drop in the water temperature or irregular gurgling sounds, this might need your attention as the heater may need another round of air removal. Yes, periodic removal of air indeed plays a crucial role in the proper functioning of your solar water heater.

Also, regular check-ups for leaks, pressure inconsistencies, and possible valve defects go a long way in ensuring the lifespan of your system.

Common Queries Around Air Removal from Solar Water Heater

Common Queries Around Air Removal from Solar Water Heater

Throughout my 20 years in the field, many clients have had similar questions ‘how to remove air from solar water heater vent?’, ‘how frequently should I perform this process?’, and ‘is there a way to prevent air from getting trapped in the first place?’

Revisiting this guide whenever necessary, performing these steps quarterly, and ensuring that your system is well-sealed can answer to all these questions. Any anomalies might hint towards a deeper problem, so get professional help immediately.


In conclusion, understanding how to remove air from a solar water heater is an essential skill for anyone wanting to maximize their system’s efficiency. With a better performing heater, you can enjoy warmer showers and lower energy bills. Keeping up with the maintenance is another crucial aspect and our comprehensive guide can help you in excelling this arena. Remember, a stitch in time saves nine!

So, why wait? Start flexing your new ‘how to remove air from solar water heater’ skills today – your hot showers and your energy bills will thank you for it!

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Elliot has 20+ years of experience in renewable technology, from conservation to efficient living. His passion is to help others achieve independent off-grid living.

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