How would you like to cut $100 off your air-conditioning energy bills this summer?

If you've had your air conditioner for more than three years, chances are it needs a tuneup -- just like a car.

Air conditioners that are not properly maintained can end up costing a bundle because they're a lot less efficient.

One repairman in my area said he inspected the air conditioners in a row of town houses and found all of them operating at least one-third off their proper efficiency rating.

Depending on where you live, this could cost $100 a year on up. But it need not. With little or no investment, you can go down this maintenance checklist and make sure your air conditioner is operating up to par.

1) Check the coils in the box outside your home. If they're dirty, they should be cleaned with some sort of liquid dishwasher detergent (it should not contain ammonia) and a hose with a power nozzle.

Be careful when you do this. Your air conditioner should be shut completely off to avoid electrical shock. Leave it off for 24 hours do it can dry out.

Dirty coils can greatly reduce your air conditioner's cooling efficiency. It works harder and delivers less cool air.

2) Check the connecting hoses. If the hose with the freon coolant is warm to the touch, you might need a Freon charge. This should be done by an airconditioning contractor. Too little Freon can waste energy and harm your machine and too much can do the same. The amount has to be just right.

3) Inside your home, be sure to check your air filter. Repair people say dirty air filters can cause all sorts of havoc, cutting the cooling efficiency way down and eventually damaging the system.

4) Check the fan belts to see if they're too loose. Loose fan belts allow slippage and air is not circulated properly. There should be about half an inch of give in the belt. If you hear a squeal every time the fan starts up, the belt is probably too loose.

While you're at it, put some lubricating oil at the points indicated on the fan motor.

5) Do not close off too many air outlets or registers in your duct system. You should never have more than one-fourth of your outlets closed. If you shut down too many outlets, it puts pressure on your air-conditioning system, which wastes energy and can break down the machinery.

With a room air conditioner, your main job is to keep the filter clean and keep vines and other plants away from the air intake outside. Every three years or so, you should have a professional go over your room air conditioner to make sure it has enough Freon and the compressor is functioning properly.

You can do quite a bit of the annual maintenance for a central system yourself, but there are some things a professional should check.

Besides the checklist mentioned above (coils, Freon, filter, fan belt and ducts), the service professional should tighten all the electrical connections and make sure the compressor is functioning properly.

Get service company recommendations from friends and small business managers you deal with. A good airconditioning service contractor can save you quite a bit of money over the years. The cost of an annual inspection should run from $30 to $40 (not including Freon or ther material that might be needed).

Q. What is the cost of managing or administering the Social Security system? Private pension fund managers are not allowed to charge more than 15 percent of the income produced as their management fee. I've seen reports that show Social Security management costs exceed 40 percent of what's collected.

A. Your information is way off target. Social Security is one of the best managed agencies in government. Administrative costs are 1.3 percent of benefits paid out.

The money to pay Social Security administrators is appropriated by Congress and does not come from workers' and employers' direct contributions.

Benefits paid out are just about equal to Social Security taxes withheld from paychecks plus employers' contributions.

Social Security will be a target for reform this session of Congress, but the cost of administration is not the issue. The rising cost of benefits is the key problem.