Alpha C23

[timmy74]

Anyone had a problem with this boiler where the dhw only stays on for a short while then cuts out then restarts. Similar situation to a dhw plate heat ex being blocked but its a twin pass heat exchanger. When it happens the top light flashes orange.

Ive rang manufacturers and they said either overheat stat, aps or pcb. Only fault i found was the over heat clip was a bit feeble and it looked like the ohs wasnt getting a good contact. However the customer says sometimes they can fill a full bath sometimes only half of hot water.

PS its in a hard water area too.

 

[gas4you]

Had a similar one recently. Wouldn't fault when I visited

Eventually they called to say it had packed up completely. Turned out it was the pcb. The fan wasn't getting supplied the voltage to work, intermittently at first.

Could be similar as you are getting the orange fan/aps light on

 

[timmy74]

Had a similar one recently. Wouldn't fault when I visited

Eventually they called to say it had packed up completely. Turned out it was the pcb. The fan wasn't getting supplied the voltage to work, intermittently at first.

Could be similar as you are getting the orange fan/aps light on

Cheers mate, Alpha did mention PCB like. I checked fan venturi etc seemed clear. I would sooner that happened to me i go off altogether easier to find fault

 

[Paul Barker]

You gave the answer, hard water area.

biflow heat exchangers from all manufacturers are great in soft water areas and areas where water pressure doesn't rise too high overnight.

Not suitable for hard water area.

 

[Agile]

I would say that a thermal survey would indicate the likely cause and if the o/h stat is likely to be operating because its reaching its rated temperature.

A four pipe HE can usually be descaled if you use a messy job best in the garden with HCl or in situ with sulphamic acid solution and a small pump.

Tony