Last updated on March 16th, 2024 at 02:10 pm

Dear Dave,

I have been reading your blog at utility bill busters for a long time now, and I wanted to ask you a question. I live in a small ranch style house in illinois in the south and as you may know the weather has been absolutely scorching! We have a window air conditioner in the bedroom and one in the living room, since those rooms are the most occupied. Recently I have noticed they seem to be running all the time but not making a difference! Should I replace those and just get a central air unit? Is it more cost effective and better for the environment? What do you think?

– Monica

Hi Monica, thanks for taking the time to write in.

Central Air is usually a big investment for most people. Units, with installation range from $1500 upwards to $4000 and beyond. A big advantage you have is living in a ranch style house. Typically, central air units work really well in these houses because there is only 1 floor to cool – no need to worry about heat loss and the unit “pushing” energy up 20+ feet to a second floor register.

That said, before you jump to central air, if you want to troubleshoot the air conditioners, here’s where to start:

• Clean them, especially the coils and filter.
• Check the thermostat, make sure it is set right
• Check to make sure the condenser turns on when cooling is needed
• Make sure internal fuses are intact
• Clear obstructions from the unit
• Make sure the installation angle is correct, so water collected “drips” outside and doesn’t pool inside the unit
• Use fans, especially ceiling fans, to distribute cooled air

All homes are susceptible to heat loss. The greater the difference in temperature is between the house and the outdoors, the more heat has the potential to be lost. If you find the AC units are working but are running constantly, chances are there is excess heat being lost in your home. Do an energy audit to find the areas of heat loss. Chances are its either the insulation or windows.