Alpha CB24x keeps requiring resetting !!

[Noisey]

Hi, Hope some one can help...
Our Alpha Cb24x boiler started tripping off (`A' red light flashing) without any real known reason... Whether just central heating on or when domestic water is switched on.... Sometimes 2 or 3 resets are required to get warm water thro, for washing up...
I had boiler serviced a few weeks ago after this started (whole set of issues there with the "engineer" sent but eventually we got a service completed..)

BUT, no change from the boiler, still tripping, requiring resetting... (had to get parents to check house whilst we were away on holiday, 3 days out of 8 boiler had tripped)..
Typically this happens once or twice a day, with boiler on in mornings and evenings.....

Diagnostic info on instruction manual suggests that this is the Over Temperature switch tripping (i.e. water too hot), but service engineer checked switch with meter and found no fault - although we couldn't replicate the problem whilst he was present....although as soon as he went it tripped & required re-setting...

His advice was to wait until a component fully failed but other wise he couldn't suggest a fault...
I replaced the flow switch today, just to see if that may effect it - as they are cheap enough on Ebay, although the old switch works ok with a meter...

Any idea's ?...

Oh, our diverter valve looks as good as new, no external leaks or corrosion.... I am wary of stripping anything plumbing wise to avoid leaks & creating seperate issues....happy to replace parts if they fix the problem... I am a reasonable car mechanic, so not afraid to dismantle anything, I just have never had to drain a plumbing system..

Thanks.

 

[Agile]

I don't know why you thought that replacing the DHW flow switch would have any effect on locking out.

Did you ask for the boiler to be just serviced when you knew that there was a fault? It needed a repair!

Apart from a routine service being cheaper, those in larger firms that do servicing are usually those who are not very good at diagnosing faults. Sometimes those doing servicing do not fully check and reset some of the gas parameters.

There are a lot of possibilities and many are topics on gas settings which we don't advise on here.

Your boiler is a budget model and not seen as a terribly easy boiler to work on and many are not very familiar with them.

Tony

 

[Noisey]

When booking the service and whilst the 4 engineers that it took to complete the service, I thoroughly explained the issue with re-setting. None of the Engineers offered any possible or plausible solution.
The best answer I got was from the 4th engineer who admitted not knowing any cause but that it may be better to wait until what ever is causing it - to completely fail, then it may be more obvious.
During the service the first engineer checked gas flows and the fourth engineer checked the burner side... I have no desire to play with any gas setting or gas component.
I had hoped that it could be just a simple exchange of new part of old, whether electrical, sensor, pcb, switch or plumbing part.

The flow switch was cheap and easy, as a few threads on here suggest that the flow switch can cause issues. Nothing lost by replacing it and removing that variable...

As for dismissing my boiler as budget - I can assure you when we paid for it I would not have called it budget.... The firm I called to service it are the same firm who installed it. At the time they assured me that it more than met our requirements and would cope with additional radiators should we desire.

 

[easyflow]

There may be nothing wrong with your boiler, the problem could be down to installation.
On this model I think its one of the few that needs the flu to be slightly pointing down rather than up.
There is a flu condensate sensor that triggers lockout if water drips onto it.
If I were you I would get the engineer back and check flu angle and condensate sensor before throwing more parts at it.

 

[mcmoby69]

Check if there is a bypass fitted, and set correctly. Also do you have trv's fitted on every radiator and a room stat?

 

[Noisey]

Thanks for the suggestions guys, but would these give problems after possibly upwards of 10 years good service ?....

The first engineer checked the flue as part of the service (using a meter of sorts to check)....

 

[mcmoby69]

No,

Thanks for the suggestions guys, but would these give problems after possibly upwards of 10 years good service ?....

The first engineer checked the flue as part of the service (using a meter of sorts to check)....

No, we just like wasting our time answering inane questions with our own inane questions.
4 engineers to complete a service?
Cracking choice of firm you're using.
How much was the service?

 

[10quidgascert]

Are you sure it's not the flow switch I've known quite a few fail on these, even brand new ones.

 

[Noisey]

mcmobyn69 - trying to keep you informed of all the info, I appreciate the comments, I just may not have made it clear that the boiler was 10 years plus old...

To be exact, 3 engineers but 4 visits.... The same "cracking" firm that installed the previous boiler and the existing boiler (on what was the coldest March in a long time - 10 years or so ago) ....
To be fair the first visit, most of the service was undertaken but the "engineer" was not confident that he could remove the gas cover without damaging the seal....
So a seal was ordered & Engineer 1 made a second visit - he made lots of noise, banging boiler but was unable to remove front and left..
I complained nicely to the company and they promised to send a more experienced engineer, at no further cost, with the seal to complete service...
Second engineer arrived but he didn't have the replacement seal.... So another phone call and discussion with "supervisor" so
3rd Engineer came, at no additional cost, he was able to remove the gas burner cover, with apparent ease and without damaging the seal - Service completed - they have invoiced 2 visits + seal cost but I phoned them to get them to at least remove the price of the seal = £120...

I had hoped the service would sort the issue, see my explanations at the start of the thread...

Meagher1981 - Flow switch, cheap as chips, so replaced, no need to bleed system so it was a no brainer - but boiler still tripping..

I do appreciate any help.