Hi guys, hope somebody can help me here. I have a Vaillant VCWGB242 combicompact boiler, it runs fine except that the dhw temp fluctuates. If I run the hot tap, the boiler fires up fine then the flame goes out, then it starts up again and so on. the boiler had 3 new boards, fan and other bits last year, it cost a fortune, and when I phoned vaillant this time the 50p a minute helpline lady said it was defineatly the gas valve, given her confidence that this was the problem before I had even given her the symptoms, I thought i'd have a look myself- try and save some money. In an effort to try and sort the problem, I eliminated the circuit boards due to the fact that they have recently been replaced and changed the NTC resistor as this was badly corroded. Heres the interesting bit, if I disconnect the two top cables (spade terminals) from what I think is the dhw overheat switch (looking at boiler this is attatched to the pipe at the front, LHS, two wires at the top on spade terminals and one on the bottom) then the system runs fine, ie flame does not cut out. Obviously, I cannot leave the boiler in this state due to no overheat protection, but for fault finding purposes am I correct to assume that I need a new DHW thermostat? or could my problem be elsewhere- the dreaded board again perhaps!!
Vaillant boiler temp fluctuating
- Thread starter dominicallen
- Start date
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