Compared to all my previous cars (Audi / Mercedes) the climate control is poor, because of what I perceive as a lack of control. I think the system is powerful enough; it just doesn't do what you ask of it.
I did 50,000 miles in my last car (Audi A8) and in 4 years I never once changed the temperature setting from the value I chose the day I collected it. It just worked. With my Model S I have to adjust the temperature every time I use the car, often multiple times per journey, over a wide range of values.
An easy way to see this is by using the remote heating feature. If on a coldish day you turn on remote heating and set a temperature say 5 degrees higher than ambient then the car will heat the cabin as you'd expect. But if you keep doing this (i.e. every 30 minutes when the remote AC turns off you immediately turn it straight back on again with the same settings) then the car will just get hotter and hotter and hotter, until it's way above its target temperature.
On the other hand on a warm day the remote cooling feature is far too weak, and never reaches its target in my experience. In April my car was parked in a sunny car park in the UK (ambient temp maybe 20C but a decent amount of solar gain). I turned on remote AC, set 20 degree C target, and watched what happened. Initially the interior reading was 29. After 30 minutes when the AC turned itself off it was 25. I restarted the AC and waited a further 30 minutes - 23. Repeated and waited a further 30 minutes - 22. So after 90 minutes the car still hadn't actually got within 2 degrees of the setpoint. I suspect I could have kept running the climate control forever and it wouldn't have ever managed to reach the target setpoint.
I'm kind of surprised they even let them out of the factory like this - as far as QA tests go "in moderate weather conditions the AC can achieve and maintain any chosen cabin temperature within 30 minutes" seems like a pretty basic one to me.
OK so I was inspired to run a simple test on this (apologies in advance that all my temps are in degrees C not F
The car is sitting in the carport outside where it's been since yesterday. It's plugged in but charging finished 12 hours ago.
Time at start is 17:00 in the UK.
Outdoor temperature (according to the car) is 15.5C, interior 18C (higher than exterior because of earlier solar gain and higher temps).
Using the Remote S* app, enabled remote heating and set target temperature to 25C (which is pretty warm, but I wanted to make the car have a decent amount of work to do).
Then every 5 minutes I took a screenshot of the app to record temperatures.
And every 30 minutes when the AC turned off I immediately re-enabled it (with the same 25C setpoint).
Car was plugged in throughout so was drawing shore power to run the heating.
* Reason for using the "Remote S" app rather than the official TM one is that Remote shows you the exterior and interior temps from the car with 0.5 degree resolution, plus the interior fan speed, and it doesn't disconnect if you leave it running for a long period.
Here's the result:
I got distracted towards the end and forgot about taking 5 minute screenshots - but the final one was ridiculous.
I really can't fathom how anyone thinks this is an acceptable behaviour from a climate control system.
This obviously isn't a compressor or cooling issue at all - the car is just heating the cabin - but it's clear that there are some pretty obvious bugs in the control logic here. It's even more strange when you remember that on 2 occasions during that test the AC turned itself off and I had to turn it back on again. So twice the system came on, discovered it had a setpoint of 25 and an ambient of either 26 or 28 and yet
decided that it needed to keep heating the cabin!