DEEP Coil: A New Energy Efficient Solution

March 29, 2010

Most air conditioning and refrigeration equipment now can readily reduce compressor horsepower, fan horsepower, OEM cost, and operating cost to the consumer by 50 percent. How? Through a new coil technology.

Thermorise Inc., an independent research company located in upstate New York, is getting ready to start manufacturing fin tube heat exchangers (coils) based on an entirely new combination of tube spacing, fin density, and number of tube rows. This new coil, called the DEEP coil, uses a tube spacing of 2, 3, or 4 inches for 3/8-inch diameter tubes, a fin density of eight or less per inch, and multiple tube rows numbering between four to 12. This compares to current design practice of 1-inch tube spacing, fin density of eight to 24 fins per inch, and tube rows of one to three. So, the DEEP coil is in a completely different “envelope.”

According to Thermorise, the basic principle of the DEEP coil is to substantially reduce the airside resistance by a combination of reduced fin density and increased tube spacing. The reduced air resistance reduces fan power needed for the movement of the air. Concurrently, the increased tube spacing allows the return bends to be of much higher diameter - 2, 3, or 4 inches compared to 1 inch for the current design coils. This respectively reduces the fluid resistance in the tube bends by 1/2, 1/3, and 1/4. This results in proportional reduction in the compressor or pump power needed to move the fluid. The combined effect is reduced fan power, reduced compressor power, reduced OEM cost, and reduced operating cost to the consumer, all to the tune of 50 percent from the current level, says Thermorise. Following is a brief illustration of this new technology.

Thermorise has purchased key machinery required to produce these coils. However, the company says more funding is needed to go to the production level. Inquiries are welcome from prospective customers, as well as for a possible joint venture, partner, or other investment. Contact Hemant Kale, PE, at

Publication date: 03/29/2010