Running the heat with the top down



Is it bad to run the heat in a convertible when the top is down? Sometimes it gets cold outside so I run the heat to allow me to keep the top down as long as possible. Am I wasting gas/resources, or is this not an issue? My guess is the heat comes from the engine, so aside from a little power to run the fan I’m ok.


The heat is free. The heat from the engine is dissipated through the radiator unless you turn on the heater. This bypasses some of the coolant flow through the radiator. (The only time you would be using energy is if your car is equipped with an after-market Stewart Warner gasoline heater, but I haven’t seen one of these in a car since 1949.)


You are correct, the cabin heat is “waste heat” from the engine that would be removed by the radiator anyway. The only extra energy you are using is a few watts to run the blower, don’t worry about it.


There is no problem running the heater in an open convertible. No resources are being consumed. And BTW you are not alone; many convertible drivers use this method.


Thanks, just the answer I was hoping for!


I run my heat with my sliding glass roof wide open and my windows open about 1" when it’s chilly but sunny out. I like the feeling of the cool breeze going through my hair.


Gas-heaters were popular options for air-cooled Volkswagens, all the way up until they stopped selling them here.


Must be why they offer heated seats in corvettes. I could see that in the convertibles, but not the coupes


I prefer putting thee top down and running the heater full blast to putting the top down on a 100 degerr day. And roll the windows up, too, if it’s especially chilly.


The VW optional gasoline heater wasn’t the genuine Stewart Warner South Wind gasoline heater. This South Wind gasoline heater was a little box that hung down under the dashboard. However, you do get credit for noting that a gasoline heater was available for the VW. The first Corvair, the 1960, also had a gasoline heater. The 1961 and later models utilized a hot air heater that warmed the air by passing it over the exhaust manifold. Also, the CitiCar, a battery powered car that came out in the 1970’s after the gasoline crunch used a propane powered heater.