Imagine a hot cup of coffee sitting on a countertop. It is experiencing a relatively consistent rate of heat loss. If you place a metal fork, which is an effective conductor, in the hot coffee upside down with the tines upward, you have just dramatically increased the rate of heat loss. A cooling system removes heat from a home in this same manner. Refrigerant flows to and through two coils that look and function like car radiators. One coil is inside and one is outside. The heat is transferred to refrigerant through the first coil, and then sent to the outside coil where it is released to the air.
Every large ship has a bilge pump, because every large ship leaks. Without that pump, the ship eventually fills with water and sinks. A cooling system is designed to remove heat from your home faster than it can return, just like the bilge pump keeps the ship dry. Now, imagine yourself in a smaller leaking Jon or other flat-bottom utility boat. Would you rather bail out that leaking boat with a small bucket or a small, disposable paper cup?
When you neglect your cooling system, letting it get low on refrigerant, it's like bailing out that boat with the small paper cup. The process requires considerably more effort and energy to do the exact same work. Furthermore, all of the lubricant for a cooling system is in the refrigerant. Running your cooling system while low on refrigerant is like driving your car with practically no oil in it. A cooling system only has so many revolutions of life in it. The way to make it last 15 years instead of 10 is to keep it tuned up so it does as much work as possible per revolution.
Did I just tell any home inspector something he or she did not already know? Of course not; but guess what I did do? I successfully explained a complex mechanical process in simple terms to someone who has no clue how a cooling system works. And, I did it through the use of analogies. I also impressed on the person the value and importance of routine maintenance.
There are few feelings as rewarding as a client exclaiming, “I get it.” The best way to convey a process to someone who has no understanding of it is through the powerful analogy. Learning to use analogies is unmatched as a teaching and communication skill for home inspectors.