From my understanding from the explanation i get (am not an engineer nor have technical training) It's the gas composition and properties bro. HC gas have more mass but lesser matter than HCFC. HC gas cools more rapid than HCFC. HC gas is isopropane and isobutane based + catalyst (which allows binding of molecules given both gases have different freezing points). Ratio 1g of HC = 2.6g of HCFC.
Theoritically, if the cooling system requires 1000g of HCFC now it only needs 384g of HC. (1000g/2.6g) Therefore lesser gas also relates to lesser load on the compressor. Less load = less work = less stress = less energy usage to perform the work. (Similar like in the office)
Compressor is pulled by the belt and pulley which is drive by the engine crank. Less work for compressor = less work for engine (have extra HP) = lesser energy usage (fuel consumption & petrol) when performing the same work pulling the compressor.
When aircond is on, and compressor kicks in, engine needs more energy to maintain the same amount of power output. To adjust and compensate for the powerloss, ECU will adjust the air-fuel ratio. Energy comes from fuel, so ECU send signal making adjustment to pump in more fuel, hence richer fuel mix of air- fuel ratio. Since now lesser energy is needed, ECU sends signal making adjustment to pump in less fuel. Leaner fuel mix of air-fuel (Improvement in Air-Ratio)
Because HC gas cools more rapidly than HCFC gas, the time interval between compressor kicking in and out reduces. (inside the car, varience should be around 1 celsius.) if the temp setting is set to max cold (16 c) a raise by 1 celcius will trigger the compressor to kick in. And when it cools down again to 16 celsius or less, it will the trigger the compressor to kick off.
As a general knowledge and rule of thumb, a conti ac system at the ac louvers (blower) should be able to cool to 10c on nominal setting (lowest fan setting). 10c on louvers = 5c at cooling coil. If 5c at louvers = 0c at cooling coil which is not good at all..
Just trying my best to explain. Hope it helps. Thanks.
