See Figures 1 and 2
The only Volkswagens with an electric heater blower fan are the Type 2/1700/1800/2000 through 1979 and the Type 4, which also comes standard with an auxilliary gas heating system. The 1980 Type 2 heater fan is driven by the alternator. Do not confuse the fresh air circulation fan used on many Type 3 models, all 1971 and later Super Beetles and Type 1 Convertibles, and all 1976 and later standard Type 1 models with a heater blower fan, as the fresh air fan circulates only fresh, unheated air through the vehicle.
The auxiliary gas heating system on the Type 4 switches on when the engine is not producing enough heat for the passenger compartment. The gas heater runs on gasoline from the fuel tank and is available as an option on Type 2 and Type 3 models.
On all models, the primary heat circulator is the engine cooling fan, which directs air flow through the heat exchangers in the exhaust system and into the passenger compartment when the heating ducts are closed.
Procedures for removing the heat exchangers and heater duct assemblies are given in Engine And Engine Overhaul .