In article , Pete C
wrote:
I see. If it's to prevent kettling then a 'delay off' relay
would do, some cheap ones available he

http://www.engsurplus.btinternet.co.uk/control.automation.htm

Just wire the pump through a pipe stat - cold side of stat to
boiler call, hot side to permanent live, common to pump

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
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