A heat wheel is a rotating device used to reduce energy consumption in air conditioning by flowing hot and cold air streams through opposing halves. It balances temperatures and reduces equipment size and long-term costs, but requires adjacent air streams, cleaning filters, and maintenance. It is best used in places with a large outside air intake and an exhaust air duct nearby, but not recommended for low maintenance areas or places with extensive duct routing.
A heat wheel is a rotating apparatus generally used to reduce the energy consumed by air conditioning equipment in humid places. It works like a rotary heat exchanger, which means it is continually trying to reach thermal equilibrium. The device works by flowing a stream of hot air and a stream of cold exhaust air through its opposing halves, using these opposing streams to cool the hot air and warm the cold air.
The physical structure of a heat wheel resembles an aluminum disk and an exhaust fan placed in the center of two air ducts. One air duct has warm outside air flowing through it and the other duct releases cool air cooled by the exhaust fan. There are also filters to ensure that the air entering and leaving the appliance is clean.
The heat wheel achieves thermal equilibrium by first being cooled by the cold air directed by the exhaust fan. As its cold side rotates to meet the flow of warm outside air, it absorbs heat from the air. As the device absorbs heat from the air, the temperature of the outside airflow decreases accordingly. When the wheel returns to its starting point, it sends the absorbed heat into the cold exhaust air and is cooled down again at the same time.
The heat wheel concept operates on the second law of thermodynamics, where heat will always move from areas of higher temperature to areas of lower temperature. The appliance, by simply rotating, allows the heat to come into contact with the cold air and therefore to be transferred accordingly. This balances the temperature in two adjacent locations, cooling the warm air and warming the cold air.
There are clear advantages to using a heat wheel. The device reduces the load on the ventilation air conditioning, thus reducing energy consumption and consequently the long-term air conditioning costs. Another benefit is that it reduces the size of equipment needed to cool or heat the area. Also note that even a small heat wheel can be very effective at transferring a large amount of heat, consistent with the small size of the equipment.
However, there are also some drawbacks that need to be considered. The initial cost of the heat wheel means that start-up costs are higher than buying equipment without it. Subsequently, the apparatus requires two adjacent air streams to operate, and these air streams must be cleaned or otherwise passed through cleaning filters. Another factor is that it needs a turning mechanism to work, which in turn requires maintenance.
The heat wheel is best used in places where a large outside air intake is needed and where there is an exhaust air duct nearby. A possible situation is a new building where the air conditioning system has been deemed insufficient for the amount of air being ventilated. Another possibility is a facility where a certain amount of outside air intake is required.
The heat wheel is not recommended for areas with generally low or no maintenance, because it requires regular inspections and cleaning. It is also not suitable for places where ducts for air flows need to be routed to a large extent. The fan will consume more energy, and start-up costs will be higher, thus negating the amount of money that would have been saved by lower energy consumption for air conditioning.
Protect your devices with Threat Protection by NordVPN
