Hi folks, I am having a problem with my Alpha CB28 Combi.
It has only occured within the last month or so.
When I run the shower, a manual mixer, the boiler fires up fine. It will stay alight for varying amounts of time and will turn off. It then fires back up again within about 10-15 secs.
Obviously during this interval the shower is then running cold until the boiler fires up again.
The pump is running fine, the divertor valve and diaphram are ok, although I changed these as precaution.
I have also changed the DHW heat exchanger and DHW sensor. I have an identical spare to source parts.
I have tested the DHW stat and I 'think' am getting the correct readings according to the handbook, less than 1 Ohm continuity across the terminals.
I have changed the shower head as I thought it might not be letting the minimum of 2.5 litres per minute through, although there doesn't appear to be a drop in pressure, now I am thinking of changing the shower, never liked my one anyway.
Sometimes if you leave the shower running for say 15 mins, the boiler will stay on and all is well.
I am going to see if these problems occur when running a bath or basin / sink taps, which would suggest the theory of not enough water flow, but your help or ideas would be appreciated.
It has only occured within the last month or so.
When I run the shower, a manual mixer, the boiler fires up fine. It will stay alight for varying amounts of time and will turn off. It then fires back up again within about 10-15 secs.
Obviously during this interval the shower is then running cold until the boiler fires up again.
The pump is running fine, the divertor valve and diaphram are ok, although I changed these as precaution.
I have also changed the DHW heat exchanger and DHW sensor. I have an identical spare to source parts.
I have tested the DHW stat and I 'think' am getting the correct readings according to the handbook, less than 1 Ohm continuity across the terminals.
I have changed the shower head as I thought it might not be letting the minimum of 2.5 litres per minute through, although there doesn't appear to be a drop in pressure, now I am thinking of changing the shower, never liked my one anyway.
Sometimes if you leave the shower running for say 15 mins, the boiler will stay on and all is well.
I am going to see if these problems occur when running a bath or basin / sink taps, which would suggest the theory of not enough water flow, but your help or ideas would be appreciated.
