Window Air Conditioners

Window air conditioners are a modern day marvel. You buy it, you put in your window and turn it on and that’s it. This time of year is when you remove them from the windows and if you’re not lazy, you service them. There’s a lot you can do but the main thing is to replace the filter so that next summer you can just put it back in the window and turn it on.

But I have central air conditioning, you say. Do you want to cool the whole house when you are in one or two rooms? At night you are in the bedrooms. Zoning air conditioning is not as easy to do as with heating. Most houses with central air conditioning are not zoned so it makes sense to use a window conditioner for sheer economy. So how much do you need? The rule of thumb is that if you have 150 square feet to cool, 5000 BTUs will do the job. Air conditioners are rated in British Thermal Units (BTU). More is not necessarily better. It will cool a room faster but it will also cool it unevenly. Air conditioners should not be used like an off-on switch. Anticipate your need and turn the conditioner on early enough to give it time to cool. And set the temperature where you want it. Many people go into a room, turn the conditioner on full blast until the room is too cold and then turn it off. It’s not meant to be used that way. If you give it time, an inexpensive 5000 BTU unit will cool a larger area and cool it evenly.

Things to Watch Out For

When you install one in your window, first make sure it’s the right size. The specs of the conditioner will tell you the dimensions of the window that will handle it. You can usually find this information on the box if you’re shopping for one. Make sure the outlet in your house that you plan to use has the proper voltage and amperage. Small units typically use 120 volts. Some larger units need a 220 volt circuit with a special outlet so pay attention.

Installation Caveats.

The most significant concern is the tilt of the box. It must be slightly tilted down toward the outside so that the moisture drips outside and not inside the house. Sometimes, you don’t find out about the error until the walls are drenched with water. It the box is installed properly, it will have the appropriate tilt. Use as much of the foam strips as necessary to make sure you have a non-leaky fit.

Most window air conditioners need little maintenance. But that doesn’t mean no maintenance. Usually, there’s nothing to do the first year, maybe even the second but after that have to clean or change the filter, usually annually. At the bottom of the unit there’s a tray to catch the water. When you remove the unit is the best time to remove and clean this tray. And while the tray is off, you can vacuum the exposed parts. Then when you have it all together, clean the outside of the box before you put it away. There are other things you can do like oil the motor and cleaning the water exhaust but I think that’s asking too much, particularly if you have several units.