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Interested to know what the black valve thingy is - it suddenly started leaking (steady drip) from the top cap. I tightened it a 1/4 turn and seems fine now. It's 5 years old. Interested in what it is, and why it might suddenly start leaking. We haven't had the heating on yet so can't think of any recent plumbing/heating/hot water change that could have prompted it.
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Thanks
Hi
If its the top valve it's the pressure reducing valve if its the bottom valve it's the safety valve
Hi - thanks. Was the top valve - anything to worry about (it hasn't leaked for a week now and all seems well)?
Its a combined pressure reducing valve with line strainer and the bottom part is a pressure relief valve. Its fitted to the incoming feed on the cylinder.
Its not uncommon for them to leak where it joins the brass as they often rely on the malleability of the plastic to seal.
good news - thanks