Should you take the preventative measure of replacing that old air conditioning unit to have lower energy bills and to reduce the risk that you'll be stuck sweating it out on a hot day?

Typically, Clark has said not to rush replacing an old AC unit. But now he has to do an about-face with his recommendation.

New rules that went into effect at the beginning of the year have changed what kind of coolant you must use when replacing an AC unit. Once your old system croaks, you must replace the old coolant with high-efficiency refrigerants like R134a and R407C.

Make no bones about it, replacing an AC unit is an expensive fix and Clark doesn't want to sugarcoat that fact.

But the benefit of doing it right now is that you can get $1,500 in federal rebate money from the stimulus law to help pay for the replacement. In addition, there may also be state money available. Visit the Consortium for Energy Efficiency's website for more info on state programs.

So this is really a threefer: Federal money, state money and you'll save about one-third on your cooling bill during the summer months when you upgrade to a 15 SEER unit (Seasonal Energy Efficiency Ratio).

Remember, your taxes and the deficit will both be going up because of the stimulus law. So you may as well get a benefit up-front!