When the hot water and central heating are turned off by the controller the central heating pump continues to run and the gas boiler 'locks out'. The pump continues to run (for hours) until the boiler is reset. What is the likely cause of this intermittent fault?
pcb is main cause of problems with this boiler.if the boiler work after you reset it then pcb is the problem.these boiler should have pump over run which is proberly why the pump still runs.when off.an decent engineer will fix this.pcb are over priced.anything between £150-250.potterton are the cause of this.as am not on site cant be 100% but hopes this helps.
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