Custom Builders Chill Out with Unico High-Velocity Heating and Cooling System

Read a few issues of Custom Builder and you'll see the scope and breadth of some of the most beautiful custom homes in the United States. A big part of designing these impressive abodes is figuring out how to heat and cool them in the most efficient manner. But roughing in traditional ductwork takes up critical space. The Unico System, first developed in Chicagoland in the mid-1980s, can be a solid solution for creating an HVAC package that won't compromise the original design integrity.

The Unico is a high-velocity, mini-duct heating and air conditioning system that, according to the company, has been installed in more than 100,000 homes and businesses across the Western hemisphere. The system, says Director of Business Development Sean Intagliata, works on the principle of aspiration, in which streams of conditioned air enter a room at high speeds and gently mix with the room's existing air currents, eliminating the drafts felt from conventional forced-air systems.

The Unico System uses a network of small two-inch ducts from a 7-inch trunk line for high-speed air delivery to the home.

"The D.O.E. (Department of Energy) was trying to pigeon-hole us in the unitary heating and cooling category, and what we weren't getting credit for is the fact that the Unico is an engineered system from the blower, cooling and heating coils, all the way through the duct system," says Intagliata. In 2004, the company persuaded the D.O.E. to place the system under a new classification: small duct, high velocity.

"It's supply and return. We're moving air at twice the speed and half the volume of a traditional system," says Intagliata. "The main 'trunk line' is a 7-inch duct. Traditional main lines in a forced air system start off at about 8 by 24. So our trunk line is one-quarter of a traditional system," says Intagliata.

At the heart of the network is the modular air handler typically installed in four separate locations in the attic and/or crawlspaces. Each air handler is assembled in just a few minutes by the company's certified installers. Air in this system passes directly over the evaporator coils in the new UniChiller unit at a colder temperature (with a 20 to 30 degree greater temperature drop across its surface as opposed to the 15 to 20 degree drop in conventional coils) than in a conventional system, so the Unico system removes 30 percent more moisture in the cooling mode than conventional systems.

Heat for the ground floor is provided by a 175,000-BTU Lennox Conservator boiler, or the system can use electric heat. The unit's blower motor is centrally located in the module, directly in the air stream. The blower cabinet is fully insulated with closed-cell insulation, providing for better sound dampening.

In the real world, the Unico can come in handy. "Our company worked on a $15 million home in the Bel Air (Calif.) area that was absolutely beautiful. It took five years to build, and many parts of the home were very detailed. But a central heating and air conditioning system was not in the plan for the architect. We installed the Unico System without the big, ugly registers, and were able to preserve the natural beauty of the home," says Sauren Petrosian of Brody Pennel Heating and Air-Conditioning near Los Angeles.

In custom retrofits, the flexible mini-ducts can be routed through existing cavities in the ceilings, walls and floors. The modular air handlers and coils can be easily installed in tight nooks and crannies.

A series of 2-inch ducts running throughout the house serves as the main arteries, which relieve pressure from the trunk line to deliver the high-velocity air.

"We pride ourselves in the fact that there will be no more than two degrees difference room to room, floor to floor, in temperature," says Intagliata.

Consequently, because the unit is small and can flex with the home's design, the outlets in each room are small and subtle. The original round 5-inch outer diameter outlets are available in paintable plastic or stainable wood. Custom builders can order a slotted (½-inch high by 8-inch wide) plastic outlet for side wall applications. Once the Unico System is installed it is virtually invisible; the diffusers blend into any décor.

The UniChiller is the modular cooling component to the Unico System.

An added bonus, says Unico's marketing team member Meg Fullenkamp, is that the supply tubing is lined with sound dampening, spun-bond nylon for a quieter operation.

No matter when your home or building was built or what its physical configuration, installing the Unico System is a possibility worth investigating.

In the end, you can pull off some of the best interior designs imaginable without compromising design or architectural integrity.