O.k. I was referring to battery cooling, not to other usage of the compressor. When DC charging, in my experience also not every time when the weather is chilly or cold. Agreed, it may lead to more compressor usage. That BMW fitted a less than appropriate device isn't great.
It's strange because the tesla model 3 and y both use almost identical compressors - hanon systems I believe.
It's very rare. 0.04%.
So with 250.000 i3's produced, that is about 10.000 cars.
I'd say rpcmac's figure works out to more like 100 . . .
Sure, the less often a device is used, the longer its life will most probably be. The problem in the discussion about the AC compressor is, that we do not have reliable data. How much compressors of the delivered 250k i3 really failed? Under which circumstances? Under which climatic conditions? Did permanent DC charging increase the failure rate? In some climatic conditions it might even be a solution to make the system inop by pulling the regarding c/b, accepting that DC charging might take a little longer, because the battery management might reduce the current when a cetain battery temperature threshold is reached. After all it seems to be pretty sure that the AC of the i3 is no device that is designed to remain switched on day in and day out for comfort.Just a thought: it is true that the A/C compressor activates when nessecary, so frequent DC charging sessions may be wearing out the compressor more in the long run. It pleas for avoiding DC charging when possible, especially in warmer climates. DC charging may not be so bad for the battery but it may be for the compressor
Yes, I made a calculation mistake
but 100 failures is almost nothing, hard to believe.
No source was provided for the 0.04% failure incidence, so I'm not very confident that this is accurate.Yes, I made a calculation mistake
You are correct. I could nor find the source myself even though I posted that number. It may be incorrect and I should have qualified it to say so - but the point still holds, whether it's a 100 or 1000 units, the number is surprisingly low given all of the noise generated. Not surprising in that regard.
The last what I want to do is defending BMW in this case. But the existence of a lot of partnumbers alone does not constitute the proof for the bad behaviour of an assembly or part. Because even if the supplier of an o-ring, seal, washer or any other part changes, BMW is obliged to change the partnumber. The modification list of the compressor would be really interesting, but for different reasons BMW will keep it top secret.
