Hi all, has any one encountered the pump running for more than 12hours...How long should the pump overrun be typically? is it a timed turn-off or temperature turn-off? has any body got the overrun circuit diagram?
The overrun is on the same boiler themostat..any help would be appreciated..Thks

ash, November 2009

The pump running for hours is normally a sign that the overrun stat is faulty. It is temperature based and normally switches off once the water temperature has dropped below 100°F

John T, December 2010

FULLY PUMPED OPEN VENTED
OR SEALED WATER SYSTEM
Remove red link between 9 and SL when
fitting a time control etc (if no switch is fitted,
link will make the circulation pump run constantly

b, November 2009