In article ,
Tony Bryer wrote:
Where the floor standing CI boilers really lose it is
that when they cut out there is a huge amount of heat stored in the heat
exchanger which disappears out of the flue

A pump over-run can help reduce this effect. But yes, it makes them a
great deal less efficient during part load conditions.

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*If you try to fail, and succeed, which have you done?

Dave Plowman London SW
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