Cooling things down and heating them up isn’t a problem for the winners inThe NEWS’fourth annual Dealer Design Awards’ HVAC Light Commercial Equipment category. Flexibility and easy maintenance highlight the themes manufacturers exemplified as they competed for top honors. Emerson Network Power’s Liebert XDH grabbed the gold, flexing its cooling capacity and easy installation features. Aerco International’s Modulex Boilers modular heating units snatched the silver, highlighting easy access and modular convenience.

GOLD: Emerson Network Power’s Liebert XDH is a waterless, high-efficiency, high-capacity horizontal row cooler with a modular and scalable design that accommodates various equipment layouts.


Emerson Network Power’s Liebert XDH is a waterless, high-efficiency, high-capacity horizontal row cooler that provides cooling for electronic equipment racks, especially in data centers. This unit provides cooling at the source of the heat, drawing warmer air from the enclosure through the rear of the unit. The air is cooled, blown into the cold aisle in a distributed pattern, and then drawn into the enclosure’s air intake to cool the equipment.

The unit is intended for use with a Liebert XD pumped refrigerant cooling system that is supplied by either a Liebert XDP pumping unit or a Liebert XDC chiller. The pumped refrigerant technology operates at low pressure in the piping circuit. Its ability to cool more than 30kW per rack allows the unit to deliver cooling with approximately 30 percent less power usage.

The XDH is a modular and scalable design that accommodates various equipment layouts. It also supports consistently rising loads. Contractors stand to benefit from the flexible installation and maintenance practices required by the unit.

Its shipping pallet includes a ramp, built-in casters, and adjustable leveling feet, which all contribute to accurate and safe positioning. Once positioned, the unit can be secured, whether to the floor or adjacent racks, with the included adjustable brackets. Optional flexible piping with quick connect fittings and factory prefabricated distribution piping assembly allows units to be added or repositioned as needed.

“This product fills a needed niche,” said one contractor judge. “I like the ease of installation and capacity of the equipment,” said another.

Minimal maintenance is required to keep the unit operating at optimal levels. According to the company, maintenance is reserved for cleaning dust and debris from the cooling and circulating fins, and checking for damaged or worn parts. The controls are located on the front of the unit at the midline allowing contractors easy access.

“There truly was forethought when it came to maintenance and access,” observed a contractor judge.

SILVER: Aerco International’s Modulex boiler control panel is on the front of the unit, and enclosure panels snap off without requiring tools.


Aerco International’s Modulex Boilers provide the performance of a multiple-boiler plant in a single-compact unit, according to the company. These condensing boilers have a turndown rate of 6:1 to 23:1, depending on the unit. The independent operation of two or more thermal modules increases each boiler’s turndown range while also increasing overall reliability.

In addition to minimizing the need for redundant capacity in any project, the Modulex can support low NOX and low gas pressure applications as well as PVC venting materials.

Multiple units can be co-located for larger applications. In the event that one module is not working correctly, the remaining modules will continue to operate, helping to alleviate emergency service calls to contractors.

One of the contractor judges commented that the technology in the Modulex was good, “however, I think the real benefit is the expandability and size of each section. This really could be an excellent option in a retrofit application.”

Regardless of unit size though, all the modules use the exact same parts to meet the needs of a single 151,500 Btu per hour model.

To make things easier on contractors, the Modulex has one connection point for each service: inlet, outlet, gas, air, and exhaust.

Each unit enclosure offers combustion view ports and multiple supply/return piping and venting locations for single and multiple unit installation flexibility.

The control panel is on the front of the unit and enclosure panels snap off without requiring tools. Access to all components, including combustion view ports, is from the front/top of each waist high unit, with single motion, top lift access for inspection and cleaning.


Emerson Network Power
Liebert XDH

Aerco International
Modulex Boiler

Publication date:07/16/2007