Alpha CB24 problem

[GrahamM]

Just been looking at the above for neighbour.
Alternate light A & B flashing. Pump runs. Continuity through low water switch. Thermistors etc ok. APS open circuit.
No power to fan.
Thinking got to be the board?
Thoughts people?

 

[bewsh]

Most likely the pcb.

Checked your neutrals?
Have you checked at the pcb connection to see if you're getting power? It could be a harness issue.

 

[Alpha man]

Pcb...

 

[GrahamM]

Thanks guys. Checked as much as I can with other components, harnesses etc.
Just wanting bit of conformation I got right diagnosis of pcb. Can be more awkward when doing a favor for someone ye know and you get it wrong.
Cheers.

 

[diamondgas]

Hi Graham ...not ruling out pcb but alternate flashing tends to be low pressure switch ... did you test for 24vDC at the switch connections as per mi's? If voltage not there then to doublecheck you can temp link the switch wires out? .... Still most likely PCB from what you say though 🙂

 

[kris]

Well said diamond I've had couple alphas where the pressures just over 1 bar and looking for fault everywhere else and when open filling loop on she clicked , I couldn't believe it as I'd already changed pcb. Defo try pressure Graham.

 

[diamondgas]

I've had a good few Alpha's that need that bit more than the mi's state too kris,do exactly the same as u and 'bingo'! 🙂

 

[Millsy 82]

Hi Graham ...not ruling out pcb but alternate flashing tends to be low pressure switch ... did you test for 24vDC at the switch connections as per mi's? If voltage not there then to doublecheck you can temp link the switch wires out? .... Still most likely PCB from what you say though 🙂

That's exactly what I thought but I did think it was 240v on low pressure switch.

 

[diamondgas]

No it stated 24vDC Millsy 82

 

[Alpha man]

Just link the two orange wires of the PPS together, eleminates the PPS!

 

[abc_plumb]

I cover the London area for Alpha and this is the most common fault.
its the pcb or fan, the pcb anit cheap tho.
Only a few places stock these coz they are so expensive!

 

[GrahamM]

Was the board guys.
Cheers!