It's winter again. Every year about this time I get a raft of messages asking what they can do about the poor heating in their bug or bus.
Most don't like what I have to say :-)
The Volkswagen uses a single-pass heater. That is, air is drawn over the heat-exchangers, ducted into the vehicle's interior, then discarded. The 'discarded' is one of the Vast Mysteries of VW ownership. (Well, maybe only Half Vast :-) 'Diiscardedd means you need to provide an OUTLET for the heated air. Crack a window and you may be surprised at the volume of heated air coming from the vents.
The part people don't like to hear is that, after working my way though their list of symptoms, I have to tell about HALF of them that they either don't have stock heat-exchangers, or they don't have a stock blower housing.
The truth is, the VW has a pretty good heater, effective down to about
30 degrees on the Fahrenheit scale. Any colder than that, you may want to consider a gasoline heater, another bit of unwelcome news.But for a majority of VW owners, simply tuning up their heater can have remarkable results. How do you 'tune-up' your heater? You can start by making sure all of the tin-ware is in place and that you have a functioning thermostat and heater flaps. (More groans, along with half-baked arguments about why they DON'T need a thermostat. You need it.)
Some people have installed 'Recirculating' heaters. That's where they've installed a bilge blower -- or similar air-mover -- to take the air from the cabin and pass it back through the heat exchangers. Each pass adds a bit more heat to the air until it gets hot enough to melt plastic.. and bilge blowers :-)
So why didn't Volkswagen opt for a recirculating heater system? Because of the possibility of carbon monoxide poisoning. With a single-pass system the risk is very low but with a re-circuating system a bad connection to the heat exchangers can kill you.
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Cold weather always produces the same questions -- which have been answered many times by myself and others. Most seem determined to 'prove' their car has a bad heating system, or want some miraculous cure for a rusted-out heat-exchanger. Not gonna happen. Your bug or bus plays strictly by the rules, one of which is that you've got plenty of waste-heat. The trick is to provide the required pressure differential and the necessary ducts to get that heat where it's needed.
Cold toes in your bus? Odds are, someone has removed the lower belly tin. That guarantees you'll never see much heat at your defrosters on your feet. WITH the lower belly tin in place, the heated air is dumped into the cabin... where it looks for an exit. Crack the wind- wing and let the heat flow.
Good engineering, all the way through the system.
-Bob Hoover