Trivia - car heaters

[Mud Dog]

Some history about the origins of climate control heaters.

Most of us don’t pay it a second mind to switch on our car heaters in winter. All we know is, it’s chilly and we need feeling back in our fingers. But this was not always the case.


Portable heaters

Other than investing a lap coat the first car heaters were similar to the heaters in horse-drawn carriages: heated soapstones, hot bricks or lanterns. A lap coat was a large, thick cloth with which the driver and passengers could cover themselves. Hot bricks were a special kind of coal that burned without odour or smoke and shaped like a brick. The soapstones and hot bricks were heated in a fire before the trips. Once they were hot, they’d be placed in an iron box covered with cloth called, the heater drawer. If no more heat were desired, cold water would be poured over the brick or stone.

Exhaust heaters

To answer the lack of continuous heat, inventors turned to the exhaust heater. This device was designed to funnel some of the exhaust heat into the passenger compartments. Unfortunately, there was no way to monitor the heat, and the compartments were constantly too hot. Also, due to all the carbon pumped into the cabin, the car’s interior had to be cleaned more often.

Water heaters

Once engineers started using coolant (originally water) and radiator systems, it was easy to run the hot coolant into the passenger compartment, and into a small radiator under the dashboard. An electric fan then blew the hot air into the compartment. One of the great aspects of the water heater development was that they recognised and introduced ventilation and fresh air into the vehicle.

Seat heaters

The idea of heated seats came from SAAB. They wanted to give the driver and passengers a more comfortable ride, who complained about backache. The theory is that more driving pleasure leads to safer driving. These heated seats were also popular amongst the military troops as the extra heat offered more protection from the cold.

Modern heaters

The heaters in our cars are a lot more complex, in the sense that we can control the temperature inside, regardless of what’s happening outside. And although the whole system is more complicated than the original water heaters, the basic concept is still the same: heat from the radiator’s coolant system is used to warm the car.


Resources:

Autos Model
Ashrae Journal
SAAB History

[Mars]

Interesting. I was always impressed with the heater systems of the air cooled beetles and Kombis. Air would be circulated between the exhausts and a shroud around the exhausts and then into the cabin. It meant that you have almost instantaneous hot air in the cabin as the exhaust pipes only take seconds to heat up from start-up. The air is pushed into the cabin by the engine cooling fan and the temperature is regulated by changing the size of the opening of the valves located in the ducts bringing the hot air into the cabin.

The only real drawback was the introduction of carbon monoxide into the cabin if the exhaust pipes should develop a leak inside the shroud. Not good at all but fortunately not that common.