Just going back to the Alde system, i get this from the manual.
Saying you should change the fluid every 2 years, or 5 if the premium fluid is used.................so which fluid is used at point of manufacture, and do you guys really change the fluid every two years. Sorry if its a stupid question, but we havent had the Alde before.
Yes I do change the fluid as specified, the risk of not doing so is corrosion, not the freezing protection. IMO the corrosion of the boiler's burner "can" being in my view the main critical component, that comes as a very expensive repair.
I also since the first change at two years old went to the right specification fluid to offer a 5 year life.
The so called "Premium" is one "Approved " by VW to meet their G13 specification, [ specifically VW G13 Antifreeze (TL 774 J), the J being an important character]
A cheapish but reliable one that is readily available is Comma's GG40, this is a VW approved product, not one with weasel-ish words like "meeting G13", meeting in whos opinion, far best IMO one approved by VW.
Note the double "G", the G40 they offer is a G12++ fluid, still a premium one and fine to use, just production etc is less environmentally friendly.
All fluids meeting that G13 spec will be magenta in colour, it is part of the spec. Typically two year life fluids are likely to be in the greens and the blues. There are other 5 year fluids in the orange and stronger reds, these need specialist knowledge to safely use and top up. If it is these the system is best flushed before going to a G13.
Edit: I noticed the question, what is used at point of manufacture?
Up till MY 2020 then almost without exception dealers specified two year life fluid was used at the factory fill.
Thankfully pressure from the forums and the better elements in the industry has now got this totally stupid, environmentally flawed situation changed to a G13, 5 year life product.