Miniduct systems heat, cool efficiently

Dear Jim: We are considering installing a heat pump or central air conditioner. We currently have radiant heating. I have heard miniduct systems are very comfortable and quiet. How do they work? – Jack W.

Dear Jack: Miniduct systems are also sometimes called pressurized or high-velocity systems. They are ideal for installation in an existing home without a central duct system or in a new house instead of installing a standard central duct system.

Although they often are used for air conditioning, they are also equally effective for wintertime heating. The heating source can be an efficient standard heat pump, geothermal heat pump, electric furnace, etc. Since miniduct systems often are installed in homes with radiant heating, hot water coils can be added to provide supplemental forced air heat.

Miniduct systems use small ducts (2- or 3-inch diameter) instead of large metal ducts. The ducts are highly insulated and covered with foil. The complete insulated duct is small enough to run through an existing wall or ceiling made with stud framing.

Instead of the main blower being located in a utility room or basement, it is usually located in the attic. A large main insulated trunk duct is run along through the attic. The many small, insulated 2-inch ducts run from this long trunk duct to the individual rooms. You may choose to heat or cool just several rooms, or perhaps an addition, with the miniduct system.

In order to get enough air flow through the small ducts, the blower operates at a higher pressure than a blower using standard large ducts. This is a distinct advantage when cooling in humid climates. With the high pressure, the heating-cooling coils can be dense and three times deeper than standard coils.

This dramatically improves the dehumidification.

Instead of floor registers, the heated or cooled air blows out 2-inch diameter outlets in or near the room ceiling. There are several outlets per room. The air flows out at a high velocity, but it is very quiet. Its velocity creates an aspiration effect which mixes the heated or cooled air with the room air for more even (floor-to-ceiling) temperatures.

The 2-inch ducts have a 5-inch diameter flange. They can be painted to match the wall color or are available in brass and natural wood. For outlets in bathrooms or kitchens, long, narrow rectangular ones fit above or below cabinets.

The following companies offer miniduct central systems: Comfortpro Systems, 800-968-8905, www.comfortprosystems.

com; Energy Saving Products, 888-652-2219, www.hi-velocity.com; Mestek, 413-568-9571, www.spacepak.com; and Unico, 800-527-0896, www.unicosystem.com.

Dear Jim: I have to replace the kitchen faucet. I currently have a two-handle faucet, but I am considering installing a one-handle faucet. Is there any conservation advantage to either type of faucet? – Ken A.

Dear Ken: They both work equally well. A two-handle faucet has two valves, instead of one in a one-handle faucet, so there is a slightly greater chance it may leak over time. Also, a one-handle faucet is more convenient to use.

If you have children, a two-handle faucet may be more efficient. When a child needs cold water from a one-handle faucet, he often moves the handle toward the center. This mixes in some hot water when only cold is needed.

Send inquiries to James Dulley, Bangor Daily News, 6906 Royalgreen Drive, Cincinnati, Ohio 45244 or visit www.dulley.

com.