Q - I want to install an attractive, clean-burning gas fireplace to help heat my living room. Will the new high-efficiency ones provide much heat? Can I also install one in an old fireplace in my bedroom? F.W.

A - There are new high-efficiency gas fireplaces available that can heat your living room, if not your entire house. With the high price of firewood today, a gas fireplace is a cheaper source of heat. The efficiency of these is as high as 75 percent, probably higher than that of your central gas furnace. The new gas fireplaces have large, tight-sealing glass doors and attractive trim. Other than the lack of the crackling sound, it is often difficult to distinguish the flames of modern gas logs from real logs. Although they operate most efficiently with the glass doors closed, you can burn them with the doors open. They are also much cleaner and safer to burn.

Most new high-efficiency gas fireplaces are "zero-clearance" designs. This means that the firebox is insulated and protected so it can be installed directly against common building materials. You don't necessarily need a chimney with a gas fireplace. Some even have forced draft exhaust vents.

The heating input rating for these gas fireplaces ranges from about 15,000 BtuH (Btu per hour) to 40,000 BtuH. You can manually adjust the heat output and blower speed depending on the heating needs on a given day. An optional wall thermostat allows you to control it just like your furance.

Room air is drawn in vent openings in the bottom of the gas fireplace by a built-in blower. Then it circulates around the hot firebox and blows out upper vents into your room. Some have additional optional heat outlets so you can duct it to adjacent rooms or to your furnace duct system.

For the highest efficiency, you can purchase an optional outdoor combustion air inlet option. This minimizes the amount of heated room air lost out the flue and provides better heat distribution throughout your house. Most have electronic ignition, so within a minute you have a raging fire.

Although it is easy to install a zero-clearance gas fireplace yourself, be sure to get the proper permits and inspections. The $40 for the permit and inspections is money well-spent. You probably will have to hire a plumber or experienced serviceman to hook up the gas line for you.

Complete high-efficiency gas fireplace inserts are also available for old existing woodburning fireplaces. Another option is just installing modern gas logs. Although the heat output is significantly less, you may not have to make expensive chimney repairs as you would if you plan to burn wood.

You can write to me for UTILITY BILLS UPDATE No. 166 showing a list of addresses and telephone numbers of manufacturers of the new high-efficiency gas fireplaces and detailed specifications on several of the most efficient ones. Write to James Dulley, The Deseret News, 6906 Royal Green Drive, Cincinnati, OH 45244. Please include $1 and a self-addressed STAMPED BUSINESS-SIZE envelope.

Q - I just bought an old electric range that I am going to put in my son's apartment. Is there anything that we can do to make it use the least amount of electricity? D.R.

A - Electric ranges are very simple devices. Check to make sure that all of the burner (element) controls work properly and actually adjust from low to high. Also clean the chrome reflector drip pans or buy new ones. They are very inexpensive and can improve its efficiency. The only other spot to check is the gasket around the oven door. Your son may occasionally bake a frozen pizza and a leaky gasket wastes electricity.