Theres a manual re-set inside combustion chamber, right hand side on the flow pipe, boiler must be off to remove this cover, use a small blunt instrument to gently push the small pin which sticks out, but do not force it. it will need a call by a quallified engineer as there is an underlying problem, with either pump, pcb or thermistor.
Boiler man
March 2008
I think this is the same fault as the vaillant pro 18 which is overheat, has the electric been off lately?
gary.wright53@googlemail.com
March 2008
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