My son just bought his first house and we found the CH has a Spirotech filter on the return to the boiler. There is no external magnet though which i have seen in adverts for Spirotech - it's a black jacket on body of the filter.
Are there models without the external filter ?
When you say "only the new ones have a magnet" ... mine is a Magnabooster MB3 filter and it has the black, removable black jacket with the magnets within that the OP refers to, and that was fitted in 2013 ... however it's not identical to the one in the OP's photo so maybe his didn't have magnets from new?
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