Def sounds like diverter valve. Does this price include
call out and labour ? If yes very good, if not, then price for part about right, tho you may get it cheaper if you shop around.
sounds like the divertor valve
was your boiler manufactured before 2000?
if yes then you need 6102806 hydraulic valve
the cheapest place ive found for new part is
you can acquire same part locally but would cost more
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