The Radiator of Snafu

I should have known that the skill of past owners to do 'unexpected things' to the building would still be beyond my expectations.

We'd been working up to this slightly risk'y job - knowing how well Dell House plumbing has a knack of not cooperating and that is one HEAVY radiator.

Carefully disconnected without too much flooding.  Drained. Lugged away from the wall to remove the old wallpaper and fit the new.  Fit a retention stay (and discover there's a fireplace aperture behind that bit...), Lug back again, and connect.

Hmm.  Not filling.  How does that happen?

Ah.  It's not connected to the central heating rad circuit.  It's, bizarrely, connected to an extension of the hot water cylinder circuit...

... the disconnected, 'redundant', extension of the hot water cylinder circuit.

50:50 whether we get the floor up again and connect it, or leave it as 'art'.

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In case you're wondering why the rad still had water in it - this room being very rarely used, the rad was turned off at both ends.