Cut Your Utility Bills

Q. We have one room in our house that doesn’t get enough cooling in the summer or enough heat in the winter. What can we do to try to make it more comfortable without increasing our utility bills? — K.H.

A. Your problem is not uncommon with a central air-conditioning and heating system. It is difficult to get the proper amount of conditioned air to all the rooms in your house. With long ducts with many bends, the central air conditioner and furnace blower just isn’t strong enough.

Often, you set your central air conditioner thermostat lower to keep that problem room cool enough. This dramatically increases your overall utility bills and makes your air conditioner wear out sooner.

There are several options you have to alleviate the problem. You can buy a small specially-designed booster fan that fits over your room outlet register. This can increase the flow of cooled or heated air to that room by 50 percent or more.

This small, almost-flat register booster fan has a summer/winter temperature sensor built into it. It only runs when your air conditioner or furnace comes on. The small motor uses 25 watts so it costs only several cents per day to operate.

On the “summer” setting, it automatically comes on when it senses cool air when your air conditioner starts. For a short time after your air conditioner stops, it continues to run to pull the last bit of cool air to that room. On the “winter” setting, another sensor switches the fan on when it senses heated air from the furnace coming from the register.

Another option is using deflectors over the registers. Often, by directing the cooled or heated air out into the room, you feel more comfortable. One effective type of register deflector is tapered to produce a “jet” or “rapids” effect. This speeds up the air flow for better distribution and the cooling effect of a breeze.

You should check the duct dampers in your basement. The damper in the duct leading to your problem room should be completely open. If you have a room that gets too cool, you can close that duct damper a little. This directs more cool air to the rest of your house.

Don’t close many dampers too far when you are air-conditioning. Central air conditioners need a lot of air flow through the evaporator coils to operate at peak efficiency. Air flow is not as critical for your furnace, so you can adjust the duct dampers more aggressively in the winter.

You can write to me for Utility Bills Update 311 showing information and manufacturers of automatic register booster fans, register air deflectors, instructions for adjusting duct dampers, and a chart showing the savings by setting your air conditioner thermostat higher. Please include $1 and a self-addressed business-sized envelope. Send to James Dulley, 6906 Royalgreen Drive, Cincinnati, Ohio, 45244.

James Dulley studied energy management at the doctoral level at Harvard.