- Joined
- 23 Jan 2007
- Messages
- 2
- Reaction score
- 0
- Country
** Vaillant VCW Gas, internally flued, approx 20 years old **
We've recently had it serviced, including having the heat exchanger fins removed & washed clean of debris. A new thermocoupler was installed too. It then worked fine for approx 3 weeks.
Now it just shuts itself off, including the pilot. Sometimes this takes an hour to happen after firing up, sometimes within seconds of firing up.
This problem happpens 70% of the time. If there is any pattern, the morning cycle (HW only for an hour) runs just fine but when the CH comes on, clunk, off it all goes. You can relight the pilot just fine but, if either CH or HW is on, clunk off it goes within 30 seconds of it firing up.
I noted a couple of posts here on either checking pushing the reset button (no difference) OR a microswitch behind the red button (not willing to take it apart) OR a blockage or misfunctioning valve slowing the flow, thus overheating the water (wouldn't know where to start, though I do note the rads get very hot when working so I don't think sludge is the answer)
Any thoughts before I spend yet more money (sigh ...) on a service call ? Is there anything I can check ?
Also - one for the legal experts - this boiler is 20 years old. It is internally flued to a large chimney stack & is well-aired. Is it true that you can no longer have internally flued boilers, even to a chimney ? It worries me that if this model cannot be fixed, I am up for £1000s to replace not only the boiler but re-plumb everything to an outside wall.
TIA - David
We've recently had it serviced, including having the heat exchanger fins removed & washed clean of debris. A new thermocoupler was installed too. It then worked fine for approx 3 weeks.
Now it just shuts itself off, including the pilot. Sometimes this takes an hour to happen after firing up, sometimes within seconds of firing up.
This problem happpens 70% of the time. If there is any pattern, the morning cycle (HW only for an hour) runs just fine but when the CH comes on, clunk, off it all goes. You can relight the pilot just fine but, if either CH or HW is on, clunk off it goes within 30 seconds of it firing up.
I noted a couple of posts here on either checking pushing the reset button (no difference) OR a microswitch behind the red button (not willing to take it apart) OR a blockage or misfunctioning valve slowing the flow, thus overheating the water (wouldn't know where to start, though I do note the rads get very hot when working so I don't think sludge is the answer)
Any thoughts before I spend yet more money (sigh ...) on a service call ? Is there anything I can check ?
Also - one for the legal experts - this boiler is 20 years old. It is internally flued to a large chimney stack & is well-aired. Is it true that you can no longer have internally flued boilers, even to a chimney ? It worries me that if this model cannot be fixed, I am up for £1000s to replace not only the boiler but re-plumb everything to an outside wall.
TIA - David