Ask any driver here in the Valley Of The Sun what the most important feature is on their car and many would probably answer, "My air conditioning!" It might be hard to argue that point. :) A lot goes into delivering ice cold air when you push that A/C button, or hot air for that matter. That's when the HVAC system in your car kicks in. Most HVAC concerns occur when you least expect it, and often at the most inconvenient times. No heat to defrost the windshield? Roasting in the summer heat? The vehicle's heating, ventilation and air conditioning system is composed of three sub-systems that all work together to provide conditioned air to the vehicle cabin. The heating part takes heat from the engine coolant and transfers it to the incoming air. The ventilation part moves and directs the air within the cabin. And the air condition part cools and dehumidifies the air within the cabin. When they're working normally they keep you comfortable during all weather conditions. Key components of the heating, ventilation and air conditioning system include: - Heater Core - Thermostat - Blower Fan - HVAC Controls - Condenser - Compressor and Evaporator Leaks, worn or malfunctioning components can cause a loss of heat, poor or no air flow, insufficient cool air, noises or objectionable odors. Coolant leaks can also cause engine overheating which can severely damage the vehicle's engine. Let take a deeper look into all these systems. Watch the video below.