ANAHEIM, Calif. - For many consumers who want better heating and cooling control over specific areas in their home, zoning is the way to go.

Contractors are beginning to realize that zoning technology can provide valuable benefits for homeowners looking to solve pesky inconsistencies, such as bedrooms that are too cold and living areas that are too warm. As contractors are offering more consumers the option of zoning, manufacturers are finding new ways to further perfect zoning through new product offerings.

Some of these new developments were on display at the 2004 International Air-Conditioning, Heating, Refrigerating Exposition (AHR Expo).

More Zoning Capability

EWC Controls Inc.( used the expo to introduce attendees to the company's BMPlus 3000 Series control panels, which are capable of linking three zones together. The controls can be used with an XM-2 expansion panel to link up to seven zones together. The BMPlus 5000 Model can link up five zones, while the BMPlus 7000 unit links up to seven zones.

According to the company, the panels are also compatible with single-stage, two-stage, dual-fuel, and heat pump systems. A dual-fuel kit is not needed for the system to be compatible with dual-fuel heat pumps, the company said.

Zone-A-Trol ( recently developed two new zoning systems. The Mastertrol Zoning System-4 (MZS4) is capable of operating four zones at a time. Its features allow the use of single-stage thermostats to control up to two-stage heating and cooling and simple heat pump thermostats to control heat pumps.

The system can also be used with the company's Add-A-Zone® Model MZA. The MZA (available as a two-zone panel) can be added to expand any MSZ4 panel to an almost unlimited number of zones, the company said.

Zone-A-Trol also recently unveiled its Mini-Mastertrolâ„¢ Zoning system (MMZ). The MMZ panel is a two- and three-zone, single-stage heating and cooling control panel. The electric panel works with all standard heating and cooling thermostats. According to the company, the Mini-Mastertrol was developed to use a minimum number of wires to make installations easier and more affordable. Each zone uses a standard four-wire thermostat.

Also, the MMZ is said to be able to control any gas-oil or electric-heating furnace, with or without cooling, and zone hydro-air systems using a hot water coil in a cooling air handler.

Aprilaire ( launched its expandable Zoned Comfort Control system, which can now control up to 12 zones. The system also offers multiple pressure-relief strategies, including static pressure-controlled bypass, barometric pressure, and controlled pressure relief. Round dampers are available in diameters from 6 to 20 inches. Rectangular dampers are offered in 8- by 8-inch to 30- by 30-inch sizes.

DuroZone ( launched its Multiline JTZ-HP system, a zone-control panel specifically for heat pumps and designed for unique heat pump applications. The JTZ-HP can control three or more zones on a single unit, and is compatible with battery-operated, hard-wired, or battery-backup thermostats. Expansions can be used beyond three zones, and no fossil fuel kit is needed, the company said.

Dennis Laughlin, general manager, Arzel Zoning Technology Inc., demonstrates the company’s new modulating bypass control designed specifically for variable-speed systems. (Photo by Jim Johnson.)

Zoning Dampers, Bypass

DuroZone also introduced its RD Damper Round zone damper. The damper is designed for use with flexible or round ducting, and is constructed of galvanized steel with reinforcing beads. The motor works with all existing 24-V thermostats.

For installation, the damper is attached to the ducts by the use of nylon ties or screws. According to the company, the single-blade design of the damper helps to ensure smooth operation and efficient sealing for better airflow control.

Models are available in lengths from 9 through 19 inches. The diameter of the RD damper runs from 5 through 18 inches.

Arzel Zoning Technology Inc. ( gave expo attendees a look at its ModuPassâ„¢ modulating bypass control. According to Arzel, zoning systems work better with the ability to ramp up or cut back blower speed. In the past, bypasses that hunted to relieve static pressure would sometimes cause the motor to ramp up and down. Arzel believes it has solved this with the ModuPass. The system uses true damper modulation for more even static pressure control. It stops the motor and bypass from chasing each other, the company said.

Zone Controllers

Australian companyInnovative Air Systems( developed several new zone-control thermostats. The Smartzone uses variable air volume (VAV) to shift air conditioning capacities where they are needed most. The consumer sets the temperature and the controller does the rest.

The Multipoint unit is an on-off zone control system that can be used to control multiple zones from a central location in the home. The Switchpoint operates like a light switch. Consumers can turn off and on the heating and cooling for several different zones. The Singlepoint operates like the Switchpoint, but comes with a spill-air safety function, which prevents compressor damage due to low airflow, the company said.

Finally, the Zonestar is a singe-zone temperature controller. According to IAS, temperature-based zoning provides the highest power efficiency.

Publication date: 02/23/2004