Water pump running constantly!

27 Feb 2008
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United Kingdom
Hi guys.

My water pump is running constantly. I have a Potterton Kingfisher MF on gravity HW and pumped CH. No valves or tanks stat.
I have noticed my pump is running constantly (it could well have been like this since i moved in to the property 1yr ago). The pump is controlled by the boiler and the connection seems to be permanently live on the boiler side. Also the boiler occasionally fires itself up for no reason.
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As you have your boiler doing gravity hot water the pump should be wired externally, the pump is wired directly to the boiler when using fully pumped systems.
Does this mean that there should be no wire whatsoever in the pump live teminal in the boiler?
yep thats exactly what it means, the pump/ boiler should be brought on by the room stat wired into a wiring centre external to the boiler.
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Thanks Picasso, there is an external wiring centre so either the pump live is wired into this or directly to the pump. Do you mean that the pump should get its power from the mains terminal through the external wiring centre. Sorry to be a pain in the neck.
You need to find out how the pump is wired, is it wired directly to the pump connection in the boiler or is the pump controlled by the room stat?
I'll take a look tomorrow in the light. But something is wired into it. so from what you have said it is wired incorrectly. I'll get back, thanks
Right it seems that the pump live from the boiler goes into the external wiring centre then off to the Pump (see external wiring pic It's the Brown and black connected by the chock block).
So it's wired incorrectly. Could this be a work around> i have noticed there is no CH out, DHW out, DHW off out terminals (optional extras) in the boiler. Which i think should be in place for gravity hot water.

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