We are independent & ad-supported. We may earn a commission for purchases made through our links.

Advertiser Disclosure

Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.

How We Make Money

We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently from our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is a Thermal Valve?

Patrick Wensink
By
Updated May 17, 2024
Our promise to you
About Mechanics is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At About Mechanics, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

A thermal valve is a valve that responds to a change in temperature, and it typically is used to help machines that deal with high pressure or flowing liquids to avoid breaking down. There are two major types of thermal valves, expansion and relief. Both types of these small components perform similar tasks but, they do so in vastly different ways. Thermal valves are found in everyday household items ranging from pressure cookers, refrigerators and air conditioners all the way up to complex industrial machines. Without these simple valves, all of those items mentioned would be bigger safety hazards and might not be part of everyday life.

The expansion type is the most common variety of a thermal valve. It is responsible for the flow of cooling liquid within many refrigeration and air conditioning units. The valve opens and closes depending on the temperature of the machine in which it is installed, allowing only a specific amount of coolant to pass. The key to the thermal expansion valve's success is its temperature-sensing bulb.

A temperature-sensing bulb is a small gas-filled bulb directly attached to the thermal valve. The bulb senses changes in temperature and adjusts the valve accordingly. When the temperature lowers, the valve closes, allowing less fluid to cool the unit. When the unit heats up, the valve opens, sending more coolant in order to reduce the temperature.

Expansion valves also are renowned for helping to increase efficiency. This unit automatically adjusts to keep itself at a specific temperature, so there is little wasted energy from unnecessary cooling. The valve keeps the unit at a consistent temperature, so a refrigerator uses less electricity.

Another common type of thermal valve is the relief valve. This offers a more simplified operation than the expansion valve but still opens and closes in order to allow passage. In the case of a thermal relief valve, it restricts the passage of hot gas vapor from pressure buildup. One of the earliest examples of this valve comes from the 1600s and the invention of the pressure cooker, which has a gas-releasing valve built into the lid.

The pressure cooker's thermal valve has a spring, rather than a bulb, as its sensitive element that controls the opening and closing. When the pressure in the valve gets too great, the spring presses down and opens the valve until enough vapor escapes to lower the pressure to an acceptable level. This release helps ensure that highly pressurized machines, such a heating system's boiler, can operate safely by keeping them from exploding.

About Mechanics is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Patrick Wensink
By Patrick Wensink , Former Writer
Patrick Wensink, a bestselling novelist and nonfiction writer, captivates readers with his engaging style across various genres and platforms. His work has been featured in major publications, including attention from The New Yorker. With a background in communication management, Wensink brings a unique perspective to his writing, crafting compelling narratives that resonate with audiences.

Discussion Comments

Patrick Wensink

Patrick Wensink

Former Writer

Patrick Wensink, a bestselling novelist and nonfiction writer, captivates readers with his engaging style across various...
Learn more
About Mechanics, in your inbox

Our latest articles, guides, and more, delivered daily.

About Mechanics, in your inbox

Our latest articles, guides, and more, delivered daily.