Condenser
The outside part of the A/C system where the freon gas is compressed back into a liquid.
Compressor
The primary component of the condeser that pumps the freon throughout the cooling system.
Freon
The refrigerant gas used to transfer heat. Usually R-22 in residential applications.
Evaporator
The part of the A/C that actually gets cold and is located inside the house. This is where the liquid freon provided by the compressor is converted to a gasious state before returning to the condenser.
Drain Pan
Collects condensation from the evaporator and drains it into drain lines.
SEER (Seasonal Energy Efficiency Ratio)
Higher ratings have lower operational costs.
Ton Or Tonnage
One ton equals 12,000 BTU's. This is a unit of output measurement for mechanical equipment.
Disconnect
The primary electrical supply located outside near the condenser. This is used to turn the unit off for service.
Transition
A small chamber (usually sheet metal) that connects furnace to evaporator.
Plenum
A chamber (usually sheet metal) where conditioned air is discharged into duct work.