trianco eurostar 65 oil boiler ignition transformer problem

can anyone help me with a problem that keeps happening with my boiler. This year i have had to fit a new ignition transformer to my boiler 3 times. can anyone tell me why it keeps going.
i have heard the boiler going on and off a bit but i know this is down to a blocked nozzle which i replaced. but twice now this year i have replaced the nozzle to find that a week later the transformer has gone.
when i replace the nozzle the boiler sounds perfect. this is starting to get anoying and expensive.
i have got someone coming to service my boiler but after the last two people who i have got to service it i have found i seem to know more about it myself. only problem with me doing it myself is i dont have the equipment to test the combustion.

It could be a poor flame.
Maybe a dodgy control box.
Perhaps a duff photo cell.
The Tranny is definately working too hard.

If the nozzle keeps ferkin up you need a decent paper element filter fitting on the oil supply.

I am assuming that you have a vertical balanced flue fitted to your boiler, if so,the problem is that the inner flue pipe is not sealed correctly to the cumbustion chamber. This will cause the cumbustion products to re enter the boiler via the outer flue, this in turn will result in the oil burner being starved of air and will cause it to continually try to fire up. This will mean that the ignition transformer is working almost none stop and therefore burn out. I therefore suggest that you check this seal and afterwards check that the air intake is set according to the burner instruction book.

If your boiler is not a balanced flue type then get back to me so that I
can give you further advice

Good suggestions, any one of TWF's suggestions is viable. What Spraggo is talking about would be evident if the flame was continually failing, which you can easily check if you know what you're looking for. Get an OFTEC engineer in

yesterday i cleaned the electrode probes and checked all the connections and everything tested out ok. and the boiler run ok last night. But this morning i have woken up to a cold house again with another burnt out transformer.
i have an open flue. the waste gases go up my chimney.
the flame dosent seem to be going out because this morning i started the boiler and after it had lit i removed the new ignition transformer. the boiler then run ok for nearly 45mins until the system was up to temperture.
i am going to run the boiler like this till the engineer comes tomorrow. its costing too much like this.

This indicates that you have a faulty contol box which is not switching of the igntion once the flame is established]