Worcester 24CDI Fault.

[gregsi1]

Hi, my boiler packed up a couple of days ago. I have had a plumber look at it but he said it is an electrical fault which he cannot find. There is no hot water/heating atall, when you turn either on the boler calls for hot water but then nothing else and after approx 15 seconds the red light starts flashing. There is no power to the fan which i am informed means nothing else will work. I have checked both fuses inside the PCB and they're ok but after that i'm lost. Should i just call a boiler specalist and if so are british gas a good bet?

 

[Plucky]

British gas will cost you alot more than an independant guy.

whats your location someone on here may be able to look at it for you.

 

[gregsi1]

Hi, i forgot to put that small detail. I live in Preston, Lancashire.

 

[tackleburger]

No pwer at fan? Do you hear the fan stat then stop? Does it not come on even a bit. Worth checking condensate trap on these I had two which I though were fans/Pcbs initially then I checked the condensate and found the choked up

 

[dontknowitall]

Presumably your plumber checked the pump, zone valves, programmer to make sure these work as they should? Only asking as boilers are often blamed as having a fault when it's a different component which is preventing the boiler from heating.

 

[tamz]

What version of CDi is it. There are a few eg combi, system, regular, and they have also been out in different guises over the years

 

[gregsi1]

No pwer at fan? Do you hear the fan stat then stop? Does it not come on even a bit. Worth checking condensate trap on these I had two which I though were fans/Pcbs initially then I checked the condensate and found the choked up

The fan doesn't start atall, i'm an electrician (but know very little about boilers) and i've checked for power myself. I have traced the cable going to the fan back to the PCB and there's no power there either.

Presumably your plumber checked the pump, zone valves, programmer to make sure these work as they should? Only asking as boilers are often blamed as having a fault when it's a different component which is preventing the boiler from heating.

The programmer is ok, but as for the rest he said that nothing would work until the fan started working.

What version of CDi is it. There are a few eg combi, system, regular, and they have also been out in different guises over the years

It's a combi boiler and i think the model is RSF.

 

[Dannypipe]

The very fist part of the ignition sequence is the fan, so yousda c

 

[tamz]

With these boilers this is how it runs say for HW.

Open tap
Divertor moves to HW position
Hw demand light comes on
Pump runs
The PCB checks thermostor and potentiometer then starts ignition sequ.
It then checks pressure switch for no air (C & NO open circuit) then fan runs then APS makes (continuity).

This is as far as you are getting

Check the overheat stat.
Check the pump for 240v.
Check the APS for open circuit.

If you have the MI's follow section J on fault finding