Suprema 100 flashing red light

[wedgeheadsparky]

I've got a Suprema 100 boiler, I replaced the pcb and fan about a month ago and a couple of times in the last week it has locked out with red light flashing. The fault find says that it could be APS or flow switch fault.
I know what the flow switch is, but what is the APS, and what would be best to replace first or can I fault find a little further?

 

[ChrisR]

Did you just replace the pcb (5102160) or the whole caboodle with metalwork and wiring loom (5111603)?
APS - Air Pressure Switch, which checks the fan is working ok.

 

[wedgeheadsparky]

I replaced the lot 511603. Where does the APS live?
Thanks for your help.

 

[ChrisR]

YOu presumably have the manual?!
Check the aps opens/closes (using resistance and voltage) appropriately.

When it locks out is the pump still running - if so it's overheating. (Tho I haven't checked the fault indication llights..)

 

[baxpoti]

If you have plastic pipework in your system replace the flow switch.

If you don't have plastic pipework in your system link out the flow switch.

 

[Soggy_weetabix]

Gas Valve?

What are the symptoms of lockout?

David