you need a gas safe engineer to do a fault find and service.
that is the only safe way to deal with this.
you may have an air lock which is causing the boiler overheat, thus tripping it out - so before you call the engineer, do some bleeding and check the system pressure is within manufacturers specs............
bubblehead, January 2010
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I can answer this question...
My boiler keeps cutting out, as if gas as run out but it has,t. If I press ?