Alpha CB24x boiler keeps turning off!!!!!

[tommyg01]

I have an Alpha CB24x boiler that turns off after around 10 minutes of running hot water. The red light comes on and I have to reset and it will then run for approx another 10 minutes etc. It also does this when the central heating is turned on. I have watched/listened at the boiler during all of this and generally there is a whooshing noise and the pressure gauge goes up, then the whooshing stops and the boiler turns off and the pressure drops back down again, followed by the red light. Hope someone has some ideas on this.

Thanks

Tom

[JackBournemouth]

Sounds like an overheat issue, possible pump issue when getting hot, sludge main heat exchanger. Could be a variety of different things

[tommyg01]

Hi Jack,

I had a good look inside yesterday and the the pipes at each end of the DHW heat exchange had small leaks. I tried to tighter the nuts and shall have to see if it leaks again later, and also if it has made any difference to the running water issue.

Thanks

Tom

[diamondgas]

Well you're a brave man tightening those. Normally you threaten to do so and a leak springs up elsewhere with fright!!! LOL .... As said above initially it sounds like an overheating issue usually down to poor circulation! What light sequence do you see when the boiler cuts out? Red flashing or on continuously? Light B on or off?

[tommyg01]

Well you're a brave man tightening those. Normally you threaten to do so and a leak springs up elsewhere with fright!!! LOL .... As said above initially it sounds like an overheating issue usually down to poor circulation! What light sequence do you see when the boiler cuts out? Red flashing or on continuously? Light B on or off?

I didn't realise I was being brave, otherwise I might not have done it. The red light comes on continuously and I have to do reset. Then it will be fine for another 10 minutes and I need to do reset again. I did try something I read on this forum of having the central heating on and then running a shower and it didn't cut out. Although the heating on by itself usually only lasts 10 minutes before the red light comes on.

Tom

[diamondgas]

I didn't realise I was being brave, otherwise I might not have done it. The red light comes on continuously and I have to do reset. Then it will be fine for another 10 minutes and I need to do reset again. I did try something I read on this forum of having the central heating on and then running a shower and it didn't cut out. Although the heating on by itself usually only lasts 10 minutes before the red light comes on.

Tom

If red light is on continuously Tom then its an ignition issue. Problems with the burner, flame detection etc. Not much you can do unless you're GSR! You can however post a general whereabouts here Only registered and activated users can see links. . and see if you get any Private Messages from engineers offering their services

[tommyg01]

If red light is on continuously Tom then its an ignition issue. Problems with the burner, flame detection etc. Not much you can do unless you're GSR! You can however post a general whereabouts here Only registered and activated users can see links. . and see if you get any Private Messages from engineers offering their services

I do have it serviced by an Alpha engineer, but he is more interested in the quick jobs with high profit ie: replacing the flow switch every 2 years for £109 plus vat (in approx 5 minutes), than spending a few hours fixing bigger problems. It's due a service in a few weeks so I shall ask him again about this problem, if he is not interested then I will take up your idea of getting another engineer.

Thanks

Tom

[tommyg01]

I have an Alpha engineer that does the servicing, which is due in a few weeks, so I shall ask him again about this problem. I get the feeling it's a big job to fix and he much prefers the 5 minute repairs ie: replacing the flow switch for £109 plus vat and the 10 minute yearly service (which goes up in price every year). If he doesn't offer to fix it this time, maybe I will ask around for another engineer. Thanks for your help.

Tom

[Alpha man]

Change the Primary NTC sensor!!!!!

[diamondgas]

Change the Primary NTC sensor!!!!!

Hi Alpha man ... I thought red continuous was an ignition fault. I know the initial post sounds more like overheating but the op mentioned the red light on permanent?