Hell Freezes over – Adapting the Logan AC system for India

They say we need fire to kill fire, or heat to kill heat. However, in our case it is a cooling system which had to be powerful enough to freeze the sun, specially blended to suit Indian requirements. The cooling system is similar in comparison to the right hand drive Dacia Logan. Only the geometry has been modified to cater to the left hand drive packaging needs. The compressor used is a Sanden “SD7V16”, which is the choice of many OEM’s like Renault, Honda, VW, and BMW. The main advantage of the compressor is its high quality control and competitive pricing. For the AC hoses too we had to modify the geometry to suit the new space constraints imposed by the left hand drive layout of the car.

In the initial development phases, there were hardly any issues since the whole car was being imported, however many problems cropped up as we started manufacturing the cars here and ran them through extensive cross-country tests. They say that in case there are no issues in development, an engineer is not required! However, the issue we faced with the compressor was something quite uncalled for. In the first durability testing vehicle testing in Northern India during the winter months, we observed that for some unknown reason, the AC pressure used to drop and there were functioning problems. After deep study by the engineering team here, we realized that the culprit was ice formation in the evaporator. “Freezing” as it is called in tech speak. For this, there was a lot of discussion taking place, and it was finally decided to change the specification of the compressor. The low pressure side was set to operate at a higher pressure than earlier to counter this. The issue was resolved however, it cost us rework on around 300 cars and a lot of time and labor.

The development of the AC hoses was not smooth sailing either because issues used to pop up more frequently. The hoses are a flexible part and their design is influenced greatly by the shapes of other components in the engine bay. It is rare to get a routing part, first time right. If there is no fouling with some component or the other, you are surely in a dream! It was a great experience to sit down, brainstorm to find the root cause of the issues, and how can it be countered.

We are currently doing some modifications, which are being done as part of cost saving. These are part of an ongoing process throughout the life of the car, aimed at making the car cheaper and more value for money for our customers. Ultimately, it was a great experience being in the hot seat, so that our customers can enjoy the cool!