In article ,
John wrote:
Both were common in the '50s and '60's. The series type was often seen
in public buildings and schools - with cast iron pipes.

Long time ago I had a rented flat - part of a large house - with a
communal heating system like that. Gravity circulation and the boiler was
a non electric type - complete with clockwork timeswitch. The pipework was
a work of art with beautiful welds in places. It was only designed for
background heating of 55F on a cold day - and worked very well. Installed
in the early '50s, IIRC.

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*If one synchronized swimmer drowns, do the rest have to drown too?

Dave Plowman London SW
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