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Significant New Alternatives Policy (SNAP)

Substitutes in Motor Vehicle Air Conditioning

Motor vehicle air conditioners (MVACs) provide comfort cooling for passengers in cars, trucks, buses, planes, trains, and other forms of transportation. The MVAC end-use is unique due to use in widely varying ambient conditions, likelihood of accidents, and the location of a part of the system―the evaporator―inside the passenger compartment. All refrigerants approved for use in MVAC have associated use conditions.

Categories of Equipment

MVAC: Passenger Air Conditioning in Light-Duty, Medium-Duty, Heavy-Duty and Off-Road Vehicles
Air-conditioning systems used to cool passenger compartments in light-duty, medium-duty, heavy-duty and off-road vehicles are typically charged during vehicle manufacture and the main components are connected by flexible refrigerant lines.

MVAC: Passenger Air Conditioning in Buses and Trains
Air-conditioning systems used to cool passenger compartments in buses and trains are typically manufactured as a separate unit that is pre-charged with refrigerant and installed onto the vehicle in a separate enclosure (e.g., roof mounted). The refrigerant charge for these systems is much larger than those for other MVAC systems.