Ideal Response 120 combi - flashing LED and no heating

[bof]

On an Ideal Response 120 combi, does anyone know what a flashing "Central Heating" LED (behind the cosmetic cover) means? The symptoms are the boiler won't light if the CH is on though the pump pumps the CH water OK and the DHW works.

MTIA

[Ed Sirett]

THE stock fault for this boiler is a leaking heat exchanger. The usual presenting symptoms are that the boiler won't light because the ignition is wet.

[bof]

Thanks for the reply. The boiler lights OK when it's DHW, and the CH doesn't get hot even when the DHW is running. I'm sure the pump's OK as when I switch off the DHW there's a couple of seconds surge of hot in the CH.

[Ed Sirett]

Firstly I'm sorry if I put you on the wrong trail here. You may well have a model that has not yet eaten its heat exchanger (yet).

I don't have a manual for this model - what does it say?

[Doctor Drivel]

Check the pressure vessel charge. This goes flat quickly on these models. Check the system pressure. It has a low pressure switch, so if pressure low problems. I'm not sure if it also has a CH flow switch, if so check this.

[bof]

In message , Ed Sirett writes

I don't know, I haven't got a manual either.

[bof]

In message , Doctor Drivel writes

If the pressure's stable and, from prior experience, if the pressure does drop it won't light the DHW either.

Thanks, the CH light flashes continuously, irrespective of whether the CH/DHW/stat switch etc. are on or off, which seems to imply that there's an internal fault of some kind before attempting to run the CH.

[Ed Sirett]

There's a reset swtich somewhere IIRC.

[bof]

First thanks for all the suggestions. The cutout switch I know of is on the bottom right, but if that pops out it shuts off the DHW and the CH. This fault is something specific to the CH.