[Solved] Green Coating on Passat B5 FL AC Evaporator: Leakage or Not? NISSENS Brand & Replacement Queries

Hello, after "small" passes with leaky air conditioning I discovered something like:


Questions for people dealing with everyday climate:
1. Is the green coating on the evaporator = its leakage?
2. Evaporator which company to choose? Can be NISSENS?
3. When replacing the evaporator, do you replace the heater during the occasion?
4. Does the evaporator need to be cleaned from the "protective layer" before assembly, as it is done with the heater, so that there are no strange odors later?

If you have any suggestions for exchange, I will be happy to read them.
greetings

You have to change the evaporator, the coating is a contrast thanks to which you can not see the tightness of the uv (smaller leaks.
As for the evaporator brand, it depends on how much you want to spend, for how long,
I would not move the heater if there are no leaks, it is probably original and you will buy something cheaper and sometimes there may be a problem.
as for the protective layer, I will not answer you

Ok, in that case I am ordering the evaporator, the dryer and the choking nozzle.
Please tell me whether this sequence of actions will be good:
1. Removal of the refrigerant from the system.
2. Unsealing the system.
3. Removing the nozzle and checking it in terms of filings and impurities.
4. Covering cables from air-conditioning against access of moisture from the air
5. Replacing the evaporator, but without connecting it to the wires (without hooking the caps and dropping the gas from the evaporator)
6. Visit the "klimy service" and replace the dehumidifier there, connect everything together.
7. Checking for nitrogen tightness? If so, what pressure and for how long?
8. If it's tight, let it be a new factor.
9. What about the amount of oil in the system, after changing the 2 elements have something to add to me?

After previous adventures, I lose confidence in some of the "professionals" and would like to have at least some control over what they do, and replace the evaporator myself.

Vaporizer exchanged for Nissens, 2 evenings after work. By the way, replaced heater.