Worcester Greenstar Heatslave 12/18 constant lockout

10 Nov 2014
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United Kingdom

I have a heatslave 12/18 and it is constantly locking out.

it seems it is ignoring the water and heating dials and just heats up to a point and locksout after 10 minutes or so

The local engineer has changed the thermostat, Control Box (with the red light on) and PCB to no avail.

Any one got any ideas?
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I think you need a new engineer not just a part changer as we call someone that just changes parts that don't need changing as he doesn't know what he's doing. How much has that cost you?
nothing yet because its not fixed ;)

I get the feeling that there is something not wired in correctly.....is there any wiring diagrams for these boilers?
Guessing its an oil boiler.
You need an oil heating guy to trace what sounds like a burner fault unless its the overheat stat thats tripping. Not a chancing parts swapper as said.
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Is the burner locking-out or is the boiler over heating and cutting out on the O/H Stat?

Normally if a burner runs for 10 mins and locks out I would be looking at the oil pump solenoid. Is the oil pressure steady throughout the 10 mins it runs?

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