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It all comes down to the rating of the burner not how hot the particular gas burns, even a Sievert with a small burner won't do a boiler, for small ones something around the 7kw rating would do and double that on a big boiler .Size wise a suitable burner at 7.7kw is 28mm across so Zee's kitchen one may just be a touch too small.Also make sure you use a High Pressure regulator, a camping or BBQ with generally be low pressure, for these large burners you need a 4bar regulator to get enough gas through them.
I agree on the regulator, well worth it to get the one Seivert supplies fir the torches.