In reply to Fredt:
This was on the Kinder Log, so it's possible the Valve Chamber was something to do with the water tanks.
(The Log doesn't give any info on why Harry Hut is so called and also why Harry Moor and Harry Hut are far apart).
GEE, JOHN THOMAS (1844-1921)
A resident of the Ashes Farm and a well respected character of Hayfield. He was a member and organiser of many of Hayfield's committees and fetes etc. However, it is the Harry Moor water storage tanks that lie beneath the moor that he is remembered for most. He had the forethought to tap and collect this pure water which continuously flows down underground from the Scout. There is close to 500,000 gallons of water in these tanks under Harry Moor, which supply all the districts around Hayfield.