ACHRNEWS

Dehumidification And Reheat In One Coil

March 3, 2004
MEMPHIS, Tenn. - Whether it is to protect important high-tech equipment in computer rooms, or to protect the health of patients in hospitals, dehumidification can be a must.

According to Outokumpu Heatcraft, dehumidification is just one benefit of its newest product. The company's patent-pending Desaturation coil is designed to be "two coils in one." The product is a combination cooling-reheating coil in one common case that can both dehumidify and reheat the same air to a desired leaving air temperature and humidity level in low cooling applications, the company stated.

The new coil will debut very soon when it is installed at two hospitals, one in North Carolina and the other in Missouri.

Pictured is the new Desaturation coil manufactured by Outokumpu Heatcraft. According to the company, the coil can cool and dehumidify air, then reheat it to the desired leaving air temperature.

More Than One Benefit

According to Mark Lien, vice president of sales and marketing for Outokumpu, the new Desaturation coil has several benefits.

"The fact that we can cool, dehumidify, and reheat air to the desired leaving temperature with one connection and with no fluid pressure drop is the biggest benefit [of the product]," said Lien.

He explained that typically one coil is used to dehumidify and cool, while a second is used to reheat.

Lien explained that the use of one coil saves on energy because there is no fluid pressure drop. Also, there is no secondary source for heating fluid.

According to Outokumpu, the Desaturation coil reduces hot water temperature, water pressure drop (WPD), and air pressure drop (APD), which results in energy savings.

This is possible because of the header arrangement on the coils. According to the company, the water pressure through a coil header can account for as much as 30 percent of the total WPD through the coil. WPD is reduced by eliminating two headers and using extended return bends on the backside of the coil. The company states that because the coil has an opposite end circuit, it has rotated the last two rows of return bends in the 10-row cooling coil directly into the two rows of the reheat coil. This eliminates the need for two headers on the backside of the coil.

With reduced WPD, cost savings can be found through a reduction in pump horsepower.

Lien said that the coil helps with installation savings. The product makes it possible to use a single set of supply and return connections. There is no need for piping from a boiler to the coil. The elimination of the second coil helps with accessibility to the coil, and provides more room in the air handler.

The Desaturation coil, according to the company, eliminates moisture carryover. The company states that a common procedure used to eliminate water droplets from forming on the leaving air side of a coil is to add an additional reheat coil downstream or to install moisture eliminator plates on the leaving air side of the coil. One coil to cool and reheat, as well as dehumidify, takes care of this issue.

Just The Beginning

While the Desaturation coil will soon be installed at two hospitals, the product is still in the initial stages. Lein said that Outokumpu Heatcraft has to take its new invention through a process in order to make it as successful as possible. Part of this process is a patent that is pending with the Air-Conditioning and Refrigeration Institute (ARI).

The other part of that process is educating the industry.

"We want to get to the engineer and get this into specification," said Lien, so it can be offered as an option for a customer's air-handling unit.

Lien explained that the company also needs to educate the OEM and aftermarket sectors of the industry. "We need to get reps educated on the value that the coil adds to the job," he said.

The company not only claims that the coil can save on energy and installation time, it will also help to create the optimal environment in conditions where moisture control is essential.

For more information, visit www.heatcraft.com.

Publication date: 03/08/2004