Q: How often should I recharge my air conditioner with new freon?

A: Contrary to popular belief, air conditioners do not consume refrigerant (freon) as a car consumes oil, so under ideal conditions it would never need changing or filling. Therefore, a low freon level indicates a leak which should be repaired before adding more. While most new system connections are welded to minimize leaks, many older units (8+ years) were connected with mechanical flared fittings which can vibrate loose over the years, causing leaks.

Freon leaks are a problem because:

1. Low freon levels reduce efficiency of the air conditioner.
2. They can freeze the evaporator coil, causing it to literally ice up.
3. Freon is an Environmental Protection Agency (EPA) controlled substance, deemed hazardous if released into the environment.
4. The heart of the unit is the compressor, which is cooled by the refrigerant. Over time, low freon levels can cause overheating and premature failure of the compressor, often requiring complete replacement of the compressor or the entire condensing unit - a very expensive proposition.

Q: Recently I've been receiving calls from heating and air companies offering to tune-up my unit for a special price. I never buy from telemarketers, but I do wonder, are regular check-ups worthwhile?

A: Our company doesn't solicit over the phone, but we do recommend annual air conditioning check-ups in the spring and furnace check-ups every fall. Although regular checkups will not absolutely guarantee that a unit will continue to work perfectly throughout the season, they will reveal most small problems that can lead to major, far more expensive problems if left unattended.

Q: What does an air conditioning check-up consist of?

A: It consists of the following steps:

1. Check for proper refrigerant (freon) levels. A low level indicates a leak, to be found and repaired before adding more freon.
2. Check all electrical components and controls.
3. Clean evaporator and condenser coils, as needed.
4. Oil motors as needed.
5. Calibrate thermostat.
6. Check the condenser.
7. Check filters.

Q: Is there anything a homeowner can do to maintain the air conditioning unit?

A: Yes. The first thing to check before turning on your unit is to make sure the condensing unit located outside is not covered up. The unit needs to draw air into the system in order to have something to cool and blow out inside, but the process is hindered if it cannot pull enough air in from outside.

We're amazed how many homeowners call because their air conditioner isn't cooling their house, only to find they forgot they had temporarily stacked lawn furniture, bags of leaves and lawn clippings, etc. around their outside unit over the winter. Some people intentionally cover their condenser to "protect" it from the elements during the winter, although these units are designed for outdoor installation and require no protection at all.

Here are some basic tips:

1. Run your air conditioner for a few minutes now, before you need it. If you wait until the first hot day to discover is isn't working, you'll find yourself on a waiting list, sweltering sometimes for days before an air conditioning specialist can come to fix it.
2. Change the filters regularly. Dirty filters restrict air flow, reducing efficiency and worse case, can cause the evaporator to ice up. Disposable fiberglass filters should replaced. Electrostatic or electronic filters need to be washed regularly.
3. Be sure all access panels are secure, with all the screws in place.
4. Clean obvious obstructions such as newspaper, leaves, etc. from around the exterior of the unit.
5. Be sure the thermostat is set in the cooling mode. Just setting the dial below room temperature will not activate the air conditioning if it is set in the heat mode.

A thoroughly cleaned air conditioning unit will operate at top efficiency. However, homeowners are strongly discouraged from using a hose and water to try clean it themselves because of the very serious risk of electrical shock and possible shorting of electrical components.

Like most anything you own, you will find that regular maintenance sooner is far less costly than repairs or even replacement later.

by Kathy Maynard, reprinted courtesy of HomeAdvisor.com