Without air conditioning, human society would collapse under the weight of its own mesh tank tops. Avoid a sticky end with today's Groupon: for $39, you get a 25-point cleaning and inspection of your heating or cooling system from Oliver Heating, Cooling & Plumbing (a $93 value).

For four decades, the masters of temperature at Oliver Heating, Cooling & Plumbing have kept clients comfortable year-round with quality residential services and customer care. Harnessing cutting-edge equipment and the skills of a weather-taming ninja, Oliver's experienced temperature techs perform a meticulous 25-point heating- or cooling-system cleansing and inspection, including a compressor and wiring-connection check, contactor-point inspections, capacitor check, and voltage check. The climate controllers also check out the condenser and evaporator coils, reconfigure the main deflector dish, check the blower motor, pulleys, drain pan, gas pressure, and air temperature, among a slew of other integral inspections to assure your heating or cooling system is clear, clean, and running at its best.