vokera 80sp problems

Hi, our boiler has been playing up and we are now on our 3rd engineer coming to look at it ( first said get a new boiler (but i've heard that ours is really quite good and don't want to do that if we can help it)and second ordered some parts 2 weeks ago and hasn't contacted us since and wont return our calls).
To sum up the faults - HW and CH keep cutting out, hot water keeps running intermit cold and the boiler whistles really loudly, then cuts out. I've done searchs on here and from what other people have said i think it maybe a) that the fan need a good clean or b) the thermistor needs replacing. Just wanted to check before he comes, as he told us to get parts and he would fit them.
Hope you can help
Mel

The person who said he "was getting parts" was probably being honest in a sideways way by indicating that he had no idea of what it is.

I would also warn you against the third. I dont fully understand what you are trying to tell us. Surely he did not tell you to get advice here and buy the parts and then he will charge you to fit them?

In my view there is only one solution! Get an engineer who is prepared to offer a no-fix no-fee repair and who will identify the ONE problem and fix it. DO NOT get someone who is just going to change parts at YOUR expense because he cannot diagnose the fault.

My expectation its actually what you have suggested and that no new parts are likely to be required. But those are CORGI engineers aspects and I am not going to give advice unless you are registered.

Tony Glazier

No i have had 3 other engineers look at the problem the said they would change the domestic diaphram first. But none of them turned up after contacting them (must be a plumber thing?? ) I have spoke to this other guy who is corgi registered. And he told me sounds to be the same thing but needs to have alook. So i have told him i will order a service kit off the web, to save time. personaly i think its more an over heating problem eg. heat exchanger as it sounds as if it boiling like a kettle on both the DW/HW which both cut out at about 80c and then restart 1/2 mins later. But when he arrives (IF?) he has a power flush system which might unblock the system.