Gasoline Heaters, 914's and buses Options

[Randal]

Did 914's and buses have gasoline heaters and if so where were they and how did they work?

Love to see a picture if anyone has one.

[aircooledtechguy]

Eberspacher made the heaters for the VWs. They have since changed their name to Espar. Do a Google image search for Eberspacher models : BN2, BN4, BA4 and BA6 and you'll see all the models they used in VWs. They now make models similar to the BN2 & BN4 models Called Airtronic 2 & 4. The website doesn't list it, but they ARE available in gasoline as well; not just diesel.

They are very well designed units (even the early ones in Beetles and buses). They are just like stock HE on your exhaust and work off the same principal.

Basically you have a S/S inner flame chamber where at one end, a small amount of fuel is mixed with incoming combustion air by way of an electric fan and inner vanes. It passes by a glow plug that ignites the mixture causing the s/s chamber to heat-up. There is an outer chamber that encases the inner chamber where a large volume of air is passes by another fan. Add ducting into the car and Viola!! A warm interior that is independent of the engine running and is much warmer than the stock HE ever could be.

Just found a video that explains it better than I can. . .

There is a lot of miss-information out there claiming that these heaters are dangerous and "explode" etc, etc, etc. Those are wives-tales retold by folks who have never owned one or even understand how they work. Eberspacher units have, since the early days, had safety switches, circuits and over temp detectors that cut power to the fuel pump if they detect an over temp condition. They also have pre-run mode for about 20-30 seconds before igniting AND run-on mode of 20-30 seconds after the fuel pump is cut off which purges the flame chamber of fuel vapors so they are safe.

The VW Beetles, Type-3s, Ghias (all w/ BN2) and Things (BN4) all had their gas heaters mounted in the trunk on the left-hand side. Buses had their heaters mounted either in the left side of the engine compartment when using a BN4 (from the 50s - '78) or under the bus when using a BA6 (from '79-on through the air-cooled Vanagon years). In all those cars they were only an option in the U.S. The Type-4 (411/412) was the only car where the gas heater was standard equipment (BA4 model). It had it's heater mounted above the transmission. This hearer was only classified as a heater "booster" since all air coming into the heater first came through the stock HE, but it could run independent of the motor and was a true gas heater.