and now the cold tap will not turn. I understand that the valve will need to be replaced but I don't know what size/type I am looking for. I realise that I could remove the old valve and take it to a plumbing supply shop for a match, but it would be simpler if I could just go and get one before turning off the water/disassembling the tap. I'm just wondering if anyone in the know could tell me what sort of valve would be used in this tap.
If it's a 1/4 turn ceramic disc type then you'll need the appropriate cartridge. If its a conventional tap (which my gut feeling says it is - BS 5412 spec being 0.1 bar min) then you'll need a new tap head gear.
If the BSM was only firtted a year ago then it should have been installed with a service valve like this:
on each of hot and cold supplies. Just turn off the supply at BOTH of these (it's a mixer tap so if you turn off the cold only and remove the offending part you'll get wet from the hot side) then you can work on the tap without having to drain down. Take the bit you need to your merchant. Alternatively talk to Screwfix and ask them to supply the part you want.
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