The THERMOTRONIC climate-control system with five zones: To each their own

Jun 24, 2019
Stuttgart/Salt Lake City

The completely newly developed climate control system of the new GLS has the qualities of a very good butler: working as quietly as possible, effortless guessing the wishes of the occupants and carrying them out unobtrusively. Depending on the equipment level, two different versions of the air conditioning system are available: the standard-fit THERMOTRONIC four-zone climate control and the optionally available innovative THERMOTRONIC five-zone climate control.

As the new GLS is so quiet, the heater fan needs to be quieter than ever. Accordingly the fan motor rests on rubber bearings so that no vibrations are transferred to the housing that might lead to a noise in the interior. A coating on the air ducts additionally dampens airflow noises.

The air is then conducted to the vents after thorough filtering and temperature control according to the weather and the occupants' wishes: separately for the driver and front passenger sides and also separately conditioned for the left and right side of the second seat row with THERMOTRONIC, which also has additional vents in the B-pillars and footwells. The five-zone THERMOTRONIC adds a separate zone for the third row.

Convenient: the air conditioning system thinks for itself

In all versions, the aim of the air conditioning control system is for the occupant to choose a setting and the automatic system then creating a pleasant indoor climate at all times. This is why several sensors measure the inside and outside temperatures, the angle of the sun and even the air humidity at the windscreen, so as to prevent misted-up windows before they can disturb the driver.

In both versions of THERMOTRONIC, the control unit of the climate control system also detects poor outside air quality or receives a warning from the navigation system if the vehicle is approaching a tunnel. In both cases, the system automatically switches to air recirculation mode, and the side windows and sliding sunroof are closed.

Like a good butler, the control system also remembers the personal preferences of up to seven different, regular users and one guest.

Climate comfort in every row of seats: the five-zone climate control system

The standard of the GLS is to offer a high level of comfort for all occupants. Even with the basic climate control system, no one in the very last row has to be chilly or sweating. But if it is possible to fulfil individual requests in row or two, then why not also in row three? After all, occupants frequently have different temperature comfort zones. That is why a THERMOTRONIC with five zones is available for the GLS, which features an additional electrically powered system to realise the separate climate control request for the third seat row. Different settings also are possible for the left and right in rows one and two.

For example, when the driver lets out all passengers and continues alone, he or she can widen his personally desired climate to encompass the entire vehicle from his seat at the touch of a button. That is because he or she could be disturbed during braking or cornering by a sudden rush of cold air generated for a seat that is now empty. Cold air is heavier and like any object obeys the law of inertia and mass – and accordingly moves through the interior. That is why the GLS features the "SYNC" button for the driver.

The ultimate on request: surface heating and AIR-BALANCE

Customers living in a cold region who attach particular importance to maximum thermal comfort can opt for the Warmth Comfort Package rather than normal seat heating – which is of course also available. This includes particularly fast-acting heating of the outer seats in rows one and two and also of the front centre armrest and the four door centre panels with their armrests. Heating wires in these surfaces ensure more homogeneous and cosy warmth after entering the cold vehicle.

Even more wellness is assured by the AIR-BALANCE Package. This has two particularly clever features. One is active fragrancing of the interior: activated, deactivated and variably controlled via a separate menu in the infotainment system, a fragrance generator perfumes the air entering the interior with a pleasant fragrance from a glass flask. There is a choice of eight different, meticulously composed fragrances, such as "Forest Mood". They can be changed by replacing the flask, which is reminiscent of a high-quality perfume bottle.

In addition, the AIR-BALANCE Package has an even larger activated charcoal filter than the standard specification. It is filled with activated charcoal made from coconut shells and is able to adsorb unpleasant harmful gases from the ambient air before they reach the interior.

Yet another benefit of the AIR-BALANCE Package is air ionisation by a high-voltage ioniser in the air duct. The ioniser generates negative ions which are attracted by the mainly positively charged airborne particles. Owing to the magnetic attraction, the particles form heavier agglomerations and fall to the floor. The particles concerned are certain viruses, bacteria and spores whose deactivation measurably benefits asthmatics and allergy sufferers. Ionisation freshens the air and keeps the driver fit for longer.