Why not contact Myson and ask?

This might help: https://www.plumbase.co.uk/potterton-velaire-vitesse-10000865-3560258/explodedviews

If you know the exact Model number if your boiler you could do a search using your favourite search engine for something like "Myson Model oil pump", replacing 'Model' with your own data, and see what comes up.

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December 2021