If it’s a 20 plate it needs a dealer visit. If it’s a 70 plate it will work.
Climate timers only work if you switch it on, then get out of the car and lock the doors, though you can then get in once it’s started. The car must also be plugged in and charging, and not have a low battery level. The ‘ready’ time is more like the start time, so don’t be surprised if it doesn’t switch on until the last minute.
You can remote precondition through the Renault app too, but you need to have your car fully registered to the account for this to function correctly. This usually takes a bit of driving, and possibly a few attempts of de-registering and re-syncing with a new activation code before it comes to life. The car can be unplugged for this, but again you must not have a low battery and the doors must be closed and locked to start, but you can again step inside once it begins.
Renault’s servers are slow and not always reliable. Don’t be surprised if you press the button and there is a long delay of over a minute. Expect to see an error message to say the command wasn’t sent but in reality the car is still preheating as per your request for example.
One final note is that it doesn’t get anywhere near as hot as running the heater with the car switched on. It will start off slightly warm, but once it gets to a fairly low temperature of about 16-18 Celcius but once it reaches that it will continue to blast the fans at full power to circulate this without much extra heat so it can feel quite cold.