inspiral

Hi, I need to do a complete coolant fluid change and wonder what would be the adequate DIY steps to do this? I could find numerous youtube videos and threads on the topic and most of them are done by simply opening reservoir cap and removing the hoses on the front radiator. Then filling it up with or without vacuum kit. However, I could find videos where VCDS steps are detailed about enabling coolant bleeding before the drain and testing it after refill. Looks like the procedure could vary based on type of engine as well. So my questions: For the model and make in the subject, do I need VCDS to open valves/pumps before I want to do a complete drain? Is using the vacuum kit enough to not need to run VCDS bleeding tests afterwards? What could happen if VCDS bleeding test is not done after the change? Could I fix it with simple workarounds while using the car until I get to someone who has this tool? If I choose not to use VCDS, do I need to run the engine to reach approx. the operating 90C temperature so then stuff(pumps, valves, ??) would open automagically and I could do a complete drain? I plan to replace the heater matrix(silica bag problem most probably) and I wonder what would be the best sequence to do this? Like using coolant system cleaner first and draining the coolant, replacing the heater matrix and do some rounds of flushes before filling it with G12+? Or do the flushes before the matrix replacement? Or not do flushes at all? For reference here is my little collection on the subject: coolant change: https://www.youtube.com/watch?v=89qDpmOtC2U trick to remove air: https://www.youtube.com/watch?v=JnTUr0SEJBw using VCDS to bleed the system: https://www.youtube.com/watch?v=t854UeaUvNA Any tip is very much appreciated! Thanks!