The Bugatti Chiron has been around for more than four years and in that time, we’ve already seen several variants of the Chiron, including the Sport, Super Sport 300+, Pur Sport, Noire, Divo and even the La Voiture Noire. However, the French carmaker has more to say about its revered product, particularly about the car’s air-conditioning system.
That doesn’t sound very exciting but the company saw it fit to detail the system anyway, given the amount of engineering that went into developing it. According to Bugatti, Europeans usually feel comfortable between 21 and 22 degrees Celsius, while most Americans prefer their AC temperature to be a few degrees colder.
“For us, it’s important to ensure that the selected temperature is quickly established. But there mustn’t be any draughts. The air conditioning system is working best when occupants don’t notice it. We have to make sure there are no draughts or noise – only then does it make you feel comfortable,” explained Julia Lemke, technical coordinator for Bugatti air-conditioning systems.
“Our vehicles travel very fast. In order for the air supply to work properly at maximum speed too, we need to ensure the ventilation and air conditioning are particularly well controlled,” she added.
According to Lemke, in conventional vehicles, air is forced into the interior at the lower end of the windscreen, but in a Bugatti this only happens up to about 250 km/h. Beyond that, there is a switch to negative pressure, which requires the Chiron to have a sophisticated control system with an additional ram air flap and an optimised blower to ensure that air continues to enter the interior.
Adding more complexity to the mix is the Chiron’s streamlined exterior that allows it to reach speeds of well over 400 km/h, where a flat windscreen with an inclination of just 21.5 degrees is required, increasing the surface area of the glass to 1.31 square metres. This is significantly different from a regular car that usually has glass area of around 0.70 square metres and an angle of inclination of around 30 degrees.
What this means is the interior of the Chiron heats up more due to the higher solar radiation or solar load, which is even more severe with the optional Sky View glass roof, a popular choice among customers who order the car.
To deal with this, the Chiron models have a powerful air-conditioning compressor with a cooling capacity of up to 10 kW (13.4 hp) and two air conditioning condensers. The system is capable of compressing up to three kg of coolant per minute from a pressure of about two bar to a high pressure of up to 30 bar. Bugatti says the setup is capable of cooling an apartment in Europe measuring approximately 80 square metres.
Another consideration made during development is the placement of the compressor, as it is exposed to very high ambient temperatures due to its proximity to the exhaust system. To make sure it works as it should, another cooling system was needed to ensure the compressor is kept within safe operating temperatures.
“At first glance, our air conditioning system appears to function like a conventional system. But it’s a real challenge to perfectly harmonise the highly complex system of a small-series hyper sports car so that it works impeccably even at maximum speed and engine load,” said Lemke.