worcester 24cdi rsf

[buckley plumb]

its been one of those wks boilers seem to be getting the better of me . been to worcester 24cdi rsf today htg works ok but on hw it works for 30-60 sec then the red hw demand red light flashes quickly and the boiler has to be turned off to reset and it will then repeat the same.checked the connections on st 16 - the yellow and red wires should be 1-30 k ohms got 6.5 kohms on both colours / the violet and browns should be less than 100ohms they were 68ohms .checked the pump by trying to stall it with screwdriver that was ok / checked the plate to plate got a differential across it of 10 degrees so assume its ok / checked and set gas burner press high and low / called worcester and they said poss plate but i dont think so . tried a few times then it worked so turned tap off and on and was working left tap on for 20 mins and all was ok so definately rule out plate. just got a call saying its doing the same thing again. i dont want to throw parts at a boiler of this age anyone any ideas. could it be a thermistor fault


ant

 

[zeebeedee]

Loose connection somewhere maybe just a guess to be honest

 

[diamondgas]

Just played with a CDi today playing silly buggers ant! The heating light was flashing fast though then slow, not the hot water light, that's something different! ... h/w fast indicates a dodgy aps according to mi's!

 

[buckley plumb]

bit confused with the manual looking at it now fail point i and j are fast flashing lights cant make out which is for which light in manual hw or htg fail point i or j .the boiler seems ok in htg but faults in hw after 45 sec sometimes it works for longer.i just assumed fail point i

ant

 

[buckley plumb]

hard to determin what light the fail point refers to in manual

 

[Doodlebug]

When it fails and starts to flash, leave it and see if it resets itself. I would take a guess at the central heating sensor.


Sent from my iPad using Tapatalk HD

 

[diamondgas]

You may have a poor connection on one of the sensors or the gas valve solenoids at a guess mate? Try pulling the spade connectors of and back on on the two sensors see if they've got a good hold and both solonoid plugs on the gas valve also! I'm sure fast flashing heating neon is when you go down this road though, not fast flashing hot water light?

 

[Nostrum]

Just looked at MI.

I reckon its the board.

manual says;

does this fault only occur in one operationg mode - YES - remove fan connector from ST1 and restart boiler, after 5 deconds is there 230v from the left (N) track and right track (L) if in hot water mode? - YES - fan - NO - PCB

I'd bet its the board just based on the fact the fan should be ok if its fine on heating.

 

[Nostrum]

Boards are about £200 for these as well if I remember

 

[lexicon101]

had same problem as this last week, no hot water , but ch working fine, turned out to be one of the sensors (had the fast flashing red fail) , the yellow coloured one IIRC, was informed by owner previous engineer had stated a new pcb was required. checked the two sensor cables,one of the plastic clips was not allowing the spade to connect correctly. removed clip and tried again with just spade, worked fine , still running today. hope this helps..