worcester bosch si 2 problem

[julesverne]

went to see this the other day and it wouldnt break down whilst i was there so asked cust to make a note of what happens when it does showing her the page on manual for fault codes.

anyway she says it is running for about an hour from cold then faults to red flashing 4 times per second which shows poss faults on manual,

Code plug missing or failed.
CH or DHW Sensor fault or out of position.
Air pressure switch fault or condense in tubes.
Fan fail or stiff.
Blocked flue.
Faulty harness.
Board fault.

my feeling it is going to be the ch sensor/thermistor.

it aint the fan or flue as those were checked whilst i was there last time.
you guys know of any common faults with these. that i need to look out for?

 

[Barry98]

I doubt it will be aps , I'd go for thermistor myself

 

[splinterdream]

I have changed a lot of PCB's for this boiler for a similar fault. If you go with this take note of the gas valve position as there are two different PCB's for this model.

 

[julesverne]

i thought so myself if it was going to be the aps it would generally be a bit more random and sooner. lady is gonna run it for a for a while before i get there might just need some thermal paste but as there only a tenner anyway just gonna paste and replace it if it is the sensor.

 

[julesverne]

stayed with it for an hour today before nailing it down to the pcb. what an arse it was. worked then one the relys started clickety clicking and no voltage to fan

 

[splinterdream]

Hahaha, told ya, don't forget there is two boards for this one depending on which way the gas valve is facing.

 

[cdodds2004]

painfull when its the board, i hate it!