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TECHNOLOGY AND YOU

Improving fireplace efficiency

Methods to improve fireplace comfort, efficiency

Q: We love to use our fireplace, but the room often gets smoky and our furnace seems to run nonstop. What can we do to make the fireplace heat better without smoke, yet still watch the dancing flames?

A: Unfortunately, the typical open hearth wood-burning fireplace is one of the major energy wasters in any home. You may feel toasty warm in front of a raging fire, but it literally sucks the heated air out of the rest of your house. This is why your furnace runs so much while there is a fire.

Fortunately, there are several simple do-it-yourself fireplace improvements to increase overall heat output and eliminate the smoke. These can make it an overall heat producer that can cut your utility bills. Efficiency improvements can also enhance the appearance of your fireplace and can make it a real focal point of the room. Some new glass doors have 24-karat gold plated trim.

The four best fireplace improvements are 1) an add-on heat circulating grate, 2) special fireplace glass doors, 3) a heat radiating fireback and 4) a chimney sealing device (when the fire is out). People often don't realize that there also is a great energy loss (room air up the flue) when there is no fire burning.

A heat circulating grate is designed to extract heat from the flames and transfer it into your home. These add-on grates have a small, quiet built-in blower (only 24 dB) that draws in cool room air. The air inlet is on one side and the heated air outlet is on the other side.

As the cool room air circulates through the multiple-pass tubular grate, it picks up heat and blows out into the room. The blower motor is located on the cool air inlet side so the air inside the tubular grate is under pressure. If there ever is a small leak, smoke will not get mixed in.

You can buy standard sizes or have a grate custom fitted to your fireplace. The entire unit is hidden inside the fireplace. A shallow (less than 1.5 inches high) air inlet/outlet grille is all that is exposed under the fireplace doors.

Depending on the size of your fireplace, the heat output can be as high as 40,000 Btu. Since this is continuous heat while the fire is burning, it can easily heat several rooms without your furnace ever coming on. It is often a good idea to switch your furnace blower on, to circulate this hot air throughout your home.

James Dulley is a mechanical engineer who writes on a wide variety of energy and utility topics. His column appears in a large number of daily newspapers.

Copyright 1999 James Dulley

18 ILLINOIS COUNTRY LIVING DECEMBER 1999

For the best comfort and control, select a grate model that has a built-in thermostat and a variable-speed blower. This allows you to control heat output and sound level. For a decorative look, select one with an add-on satin brass or antique copper grille.

Tight-fitting glass fireplace doors are a must. Look for ones with special high-temperature silicon gaskets and strong latches to create an excellent seal. Some, like Wilkening Fireplaces, use cam latches that will stay closed even if large logs accidentally roll off the grate against the doors.

If you are like me and enjoy poking at the logs, select new doors with easy-to-open graphite impregnated or teflon screen slide rods. They are easy to open and close. Full-view doors eliminate the center frame section so the view is not obstructed.

A fireback is an age-old technique used often in Europe. A heavy cast-iron plate, often with decorative patterns, is set up in the back of the fireplace. This fireback gets hot and radiates more warmth out into your room.

Most fireplace dampers do not seal well and lose room air year-round when there is no fire. Try using a low-cost inflatable chimney pillow. Whenever there is no fire and the damper area is cool, push the clear plastic pillow up into the chimney. It has a long hose with a clip. Blow it up so it expands and seals off the chimney.

To reduce smoke in your room, make sure you are burning seasoned firewood. Installing a chimney fan/screen unit on top of the chimney will help. Most models have adjustable speeds to fine tune the draft. You can install one in about 30 minutes.

Always keep a window opened slightly in the room to provide make-up air when a fire is burning and especially if the chimney fan is running. You must be careful not to cause your furnace or water heater flue to backdraft.

Write for (or instantly download - www.dulley.com) Update Bulletin No. 424 - buyer's guide of 15 manufacturers of heat-circulating grates, glass doors, firebacks, chimney pillows and chimney damper/draft fans. Please include $3.00 and a business-size SASE. Mail to: Jim Dulley, Illinois Country Living, P.O. Box 3787, Springfield, IL 62708.