Boiler normally runs ok
But about every 7 days it will start up for a short while then refuse to light up any more even by changing the hi/lo switch and /or turning the boiler off at the wall timer
The hi/low switch clicks when move but no firing up
If i bang the outside casing of the boiler then it starts as normal and continues to until about another 5/7 days and i have to do it again
Any ideas please?
But about every 7 days it will start up for a short while then refuse to light up any more even by changing the hi/lo switch and /or turning the boiler off at the wall timer
The hi/low switch clicks when move but no firing up
If i bang the outside casing of the boiler then it starts as normal and continues to until about another 5/7 days and i have to do it again
Any ideas please?