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 Heat Wheel?

By I. Ong
Updated May 17, 2024
Our promise to you
AboutMechanics 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 AboutMechanics, 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 heat wheel is a rotating apparatus generally used to reduce the energy consumed by air-conditioning equipment in humid locations. It functions as a rotary heat exchanger, which means that it continually attempts to achieve thermal equilibrium. The device operates by having a warm air stream and a cold exhaust air stream flowing through its opposing halves, making use of these counter-streams to cool hot air and to heat cold air.

The physical structure of a heat wheel resembles an aluminum disk and an exhaust fan placed in the middle of two air ducts. One air duct has warm outdoor air passing through it, and the other duct releases cold air chilled by the exhaust fan. Filters also are in place to ensure that the air entering and exiting the apparatus are clean.

The heat wheel accomplishes thermal equilibrium by first being chilled by cool air directed by the exhaust fan. When its cold portion rotates to encounter the warm outdoor air stream, it then absorbs heat from the air. As the device absorbs warmth from the air, the outdoor air stream temperature consequently drops. When the wheel rotates back to its starting point, it then sends the absorbed heat into the cold exhaust air while simultaneously being once more chilled.

The concept of the heat wheel operates on the second law of thermodynamics, wherein heat will always move from areas of higher temperature to areas of lower temperature. The apparatus, by merely rotating, enables heat to come into contact with cold air and thus accordingly transfer. This balances out the temperature in two adjacent locations, cooling hot air and warming cold air.

There are clear benefits to using a heat wheel. The device lessens the load on ventilation air-conditioning, thus reducing energy consumption and subsequently the long-term air-conditioning costs. Another advantage to this is that it then lowers the size of the equipment needed to cool or heat the area. Note also that even a small heat wheel can be quite effective in transferring a high amount of heat, in keeping with the reduced size of the equipment.

There also are some drawbacks that must be considered, however. The initial cost of the heat wheel means that the starting costs are higher than purchasing equipment without it. Next, the apparatus requires two adjoining air streams to operate, and these air streams must be clean or otherwise pass through cleaning filters. Another factor is that it needs a turning mechanism to operate, which in turn requires maintenance.

The heat wheel is best used in locations where a large intake of outdoor air is needed, and where there is an exhaust air duct close by. One possible situation is a new building in which the air-conditioning equipment has been found to be insufficient for the amount of ventilated air. Another possibility is a structure where a certain amount of outdoor air intake is required.

The heat wheel is not recommended for areas with typically low to nonexistent maintenance, because it requires regular inspections and cleaning. It also is not suited for locations where the ducts for the air streams must be routed to a great extent. The fan will consume more energy, and the starting costs will be greater, thus nullifying the amount of money that would have been saved by the lower air-conditioning energy consumption.

AboutMechanics 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.

Discussion Comments

AboutMechanics, in your inbox

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

AboutMechanics, in your inbox

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