Air-conditioning coils get careful cleaning

Tag：Air Pressure Switch

My air-conditioning unit coils are dirty from cut grass and the elements. I was told to turn the unit off and spray Mean Green on the coils for a few minutes and hose it off. Is this true?

Mean Green, according to the product Web site, is a "unique blend of non-toxic biodegradable detergents" and can be used on outdoor equipment. If all you have on your air conditioner's coils is grass clippings and dirt, you can skip the degreaser and simply hose off the dirt.

If you think the coils need a degreaser, try the Mean Green, but always read and follow label directions. When working around any electrical appliance make sure the electricity is turned off at a breaker or switch.

Use a garden hose to wash the coils. Do not use a high-powered pressure washer that could damage the coils and ruin the entire unit. If the unit is open at the top where the fan can be seen, use the hose to spray the coils from the inside out through the top grill.

There are a few models with closed tops that will require removal to clean. Unless you know exactly what you are letting yourself in for, have these units cleaned by a professional.

My husband and I have bought a house, and the previous owners added a sunroom. They put in one air duct for heating and air. They did not insulate the floor. I would like to know what kind of insulation to use. Also, would we have to cover or enclose underneath?

When a room is added to a conditioned home, the existing furnace and air conditioner need to be inspected by a professional heating, venting and air-conditioning contractor to see if the units are capable of handling the additional air flow.

The original furnace and air conditioner were designed for the square footage of the original home. When a room is added, the ability of the furnace fan and the capacity of the AC to handle the extra air movement may require an upgrade to a new system. As an example, a simple 12-foot-by- 14-foot sunroom addition has about 1,344 cubic feet of space that needs to be conditioned.