Alpha CB28 troubles - ask for an advice

15 Jul 2017
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United Kingdom
I would be hugely grateful for some help with my boiler - Alpha CB28. It has some failure - it's trying to star when the water in on - sound like trying to start a fire but it goes off after 1-2 sec. Somebody advised that it could be a circuit board and that its probably better to put a new one since board replacement would be expensive. The boiler was produced in 2006 but it is being used for about 8 years. I would be grateful for suggestions what problem could it be or what to do with this?

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how did they come to the decision to replace the PCB ? what fault indication does it give with the neons on the front , if fast flash or colours ( A&B )

you need to add more details for any constructive advise;)
Many thanks AGAS and Ian for replies.
So regarding lights. When water is off B blinks with yellow about every four seconds. When the water is on, every second blink of Blight is slightly shorter. But today for the first time A was constantly on in red. I did the reset as suggested and red went off and B again started to blink yellow. But still not working.

Ian, regarding electrical work recently - about 2 months ago I was fitting new lamp in the ceiling. But it seemed to work fine without problem. Previously, few months ago I fitted few other lamps in other rooms and also some light switches with dimmers but there was also no problem with electricity that time.

So when I am turning water on there's a sound like boiler would be starting but its going off after about 1 second, and turning on again and off again the same way all the time. At that time B is flashing about every 4 seconds.

The guy who saw boiler also asked about any electrical problems recently. So basically he was watching the boiler, listening and also touching it with some electric measuring device ;) Not sure the name if it (probably digital multimeter or sth - had two cables and small screen and seemed to measure sth related to electricity).
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basically your boiler requires a 240V AC supply, Live and neutral, some boilers are fine if this has been reversed for some reason , but your boiler will not , it has to be the correct way round or you will get the symptoms that you are experiencing, your boiler will not stay alight if you have reversed polarity, can be other things but you need to get this checked first
tbh their could be a problem with the pump ( with your description ) ,have you got a multimeter and can use it , the B LED is telling you that the boiler is the electrical supply to boiler is on .

if your competent with multimeter you can check for correct polarity as IAN has mentioned
Ok. Thanks. I think that in general I will consider first repairing it before getting totally new one. This one is produced in 2006 but used for about 8-9 years but most of this time it was used by just single person so it shouldnt be overused. I was just wondering if those boilers tend to have more failures and whats their lifespan?
Just get another REPAIR engineer out to have a look for you if you can't do anything as I suspect with not answering my question (y)

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