Baxi Solo 18HE keeps locking out.

1 Nov 2009
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United Kingdom
I have a Baxi Solo 18HE boiler that over the past few weeks has been increasingly locking out (red light on) so that the reset button has to be pressed to fire the thing back up again, it is happening almose daily now. In the main, once the reset button has been pressed, the boiler will fire up without problem. Interestingly when the boiler does fire up, it does so with a surprisingly loud 'thump'. Does anybody have any idea what the fault maybe? I must admit it is a little overdue for a service and I hope this is all thats required.

Thanks in advance
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The "thump" can be sorted with a service, the over heat is probably not related to a fault with the boiler, get your service guy to check out your pump, etc.
The 'thump' is due to multiple ignition attempts therefore not likely to be overheat lock out but ignition lock out.......electrodes/lead!
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Hi thanks for the replies. Just checked the possible faults as indicated on the inside of the boiler flap. It states that if the red lock out light is flashing this indicates an overheat problem, if on constantly then its ignition. The red light is on constantly in my case, so I assume ignition and electrodes? What happens to the electrodes out of interest? They just get a build up of oxidisation or something thats prevents a decent spark?

Thanks again
The spark earths before passing through the ignition electrode and jumping across to the earthed electrode......hence multiple ignition attempts and some times explosive ignition due to gas build up.

Replace em or better yet change the door which include the new style electrodes designed to elimiate this

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