Worcester 24CDi Lockout Problem - help

Hi - I've had the same problem with my 1999 Worcester for the past 2 years now on and off.

During periods of quite high use (heating and water simultaneously) the boiler locks out and needs resetting. This is quite intermittent but can sometimes happen several times a day and is pretty annoying when the heating/dh water die.

My usual heating engineer does not have any new ideas (I believe he has tried changing the sensors) so I am wondering what the problem is likely to be and what can I do about it?

I'm in York and do not now know off the top of my head who can do the job. Help??

Ta,
Charlie

Any ideas anyone?

Thanks

When the boiler cuts out, which light is flashing? CH, HW or both and how fast are they flashing? Once a second or 5 times a second.

Your "usual heating engineer"? Really? Is he so usual that he's been investigating this problem over the last two years, and done nothing but attempted and failed to change the sensors?

What are the actual facts of the situation, rather than the subset that you want to reveal?

I'd probably be tempted to get in either Worcester or Bg as the cdi will lock out at just about anything:

Blockage
Sticking gas valve
Fan
Air pressure switch
Rectification electrode
etc, etc

But the fault light(s) will give us a bit of a clue.

Softus said:

Your "usual heating engineer"? Really? Is he so usual that he's been investigating this problem over the last two years, and done nothing but attempted and failed to change the sensors?

What are the actual facts of the situation, rather than the subset that you want to reveal?

Click to expand...

Softus - Bit tetchy no? The facts are as I've put them I'm afraid, nothing more sinister. The usual chap cannot help as he is so busy his answering machine message now at last call said "don't bother me for three months" or words to that effect. As the property is now rented I can't afford to leave it that long and as I have a LL safety check needed well before then I wanted to kill both birds with one callout!

It's the overheat lockout (flashing once a second) btw.

Hope that helps.
Charlie

cdg, techy - no; cynical - yes.

However, in hindsight you didn't deserve that. To explain, I think it about the time that I'd just had a run in with a new forum member who was being devious and manipulative in not presenting the full facts. I was wrong and I apologise.

My underlying point was that we need to know more about what your engineer has been doing since the fault first became apparent.

That's fine, no problem. I guess it happens a lot - half a story.

In this case, the full saga is that the house used to be mine, we had the occasional problem of overheat lockout so we reset it and it used to work. So intermittent as not to be a problem. At servicing time, later that year, I asked him to look into it. He couldn't recreate the problem and the service seemed to disguise the issue for a while.

It started up again later (days/weeks can't recall) but never a big issue, once every couple of weeks.

When we moved out we rented it, now, tenants aren't always the most informative of people and we found out that the problem was a lot worse only a few months after we left, occurring every day, seemingly when hot water was called for when the heating was already on. ie bath would run cold, washing up etc. They were resetting it all the time.

I got my guy to change the electrodes (his suggestion obviously). Again, some time passed but then only after a few months of me asking did the tenants say "OH yes, it's still happening".

His next suggestion was to change the PCB which is costly and didn't seem to make sense to me as it was not failing every time, all the time.

The boiler is 6.5 years old now and I wonder if it is a genuine air flow problem. Since the PCB idea which was mooted (at the time the electrodes were changed in 2005) nothing has been done to it and I don't know who to get to guarantee a fix although Bosch are looking the only option at the moment.

That's about it.