I wonder what the deal is with the boiler, Wilesco's sight says its a "With its specially optimized boiler" , I would be interested in more pictures of the underside of the boiler if possible Nick, it looks different than the one in Wilescos parts list ?
Here’s the picture from Wilesco’s store (same boiler)
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I saw that in my research, yours looks like it has 2 rows of tangs this one looks like it has a single middle row (although I don't know how it would stand upright) ,anyway in the end I had to have one & placed an order. 🙃👍