Air to air heat exchangers provide a novel and economical method of closed loop enclosure cooling. Apart from the air circulation fans, the exchangers use no energy and are relatively quiet in operation. In many instances, they offer a viable alternative to enclosure air conditioners.
Because of their unique characteristics, many people are unsure how to use them so we asked our experts to answer some common FAQs.
1. How Does An Air To Air Heat Exchanger Work?
An air to air heat exchanger uses a heat pipe to transfer heat from a hot enclosure to the cooler ambient air. The heat pipe is an evacuated tube filled with a special refrigerant liquid. This refrigerant boils when absorbing heat from the hot air in the enclosure. The resultant vapor rises to the top of the tube and is condensed by the cooler ambient air when giving up its heat. The process is continuously repeated.
2. How Much Power Do They Use?
A heat pipe uses no electrical energy at all. However, for efficient operation, small fans are required to circulate the air inside the electrical enclosure and to blow outside air over the top of the heat pipe.
3. Can They Cool Below Ambient Temperature?
No. An enclosure using an air to air heat exchanger will always be slightly warmer than the surrounding air temperature. The actual differential will depend on the heat load and the capacity of the air to air heat exchanger.
4. How Can I Calculate the Heat Removal Capacity?
An air to air heat exchanger’s capacity is specified in Watts per degree Fahrenheit (and also Centigrade) temperature difference. For a rough estimate, calculate the heat load of the enclosure in Watts and then divide the heat load by the capacity of your air to air heat exchanger. The result will give you the temperature difference between the environment and the enclosure. For a more accurate approach that considers the size and type of your enclosure and the ambient environmental conditions use a calculator that incorporates the necessary formulas.
5. Do They Require Servicing?
The only servicing that’s required is to keep the airways clean. Make sure the fan and air intake is clean and blow away any dirt that has adhered to the heat pipe fins.
6. Are They Suitable For Use In Sealed Enclosures?
Yes. An air to air heat exchanger is a closed loop cooling system that is only suitable for a sealed enclosure. Models are available to suit NEMA 12, 4, and 4X enclosures.
7. Can They Handle Wash Downs?
A NEMA type 4 or 4X air to air heat exchanger is suitable for use in environments where it is necessary to hose down equipment and to use cleaning chemicals.
8. Can I Use Them To Replace Fans In An Enclosure?
Not directly. The principle behind fan cooling is to remove heat by blowing ambient air through an enclosure, whereas an air to air heat exchanger is a closed loop cooling system that requires a sealed enclosure. If the enclosure that is being fan-cooled is suitable for sealing, then it may be possible to install an air to air heat exchanger.
9. How Are Air To Air Heat Exchangers Installed?
Air to air heat exchangers can be easily installed to the sides of an enclosure by cutting appropriate air circulation holes in the side of the enclosure. A simple template is supplied. The heat exchanger is attached to the side of the enclosure and sealed using a supplied sealing gasket. A power supply is required for the air circulation fans.
10. Can I Fit One To My Enclosure Door?
Yes, provided the door is strong enough, the enclosure is properly secured, and can support the weight of the air to air heat exchanger without toppling over.
11. Can I Use Solar Power?
Yes. The only power requirement is for the fans, and they are available for AC power as well as various 24 and 48 Volts DC.
12. Can I Use One in A Hazardous Location?
Yes. Models are available that comply with the requirements for certain hazardous locations. Contact us for further information regarding this point.
Do You Need More Information?
If you need further information on Thermal Edge air to air heat exchangers, contact our sales team who will gladly provide additional information and show you how our air to air heat exchangers can solve your cooling problems.