Recent content by marchesexile

Confidently diagnosed as defective IGNITION SEQUENCE PCB. When installed we will know the answers. I hate this contraption.

Chris, Thanks for responding! That's right - no spark therefore no ignition. Fault code F21 refers to general "non-ignition", but isn't too clear as to what might cause it. The manual advises to check gas and water pressures. I first experienced the F21 problem soon after I moved in here -...

Can anyone help with this one ? Vaillant EcoMax 236 model, 8 yrs old, at that time new installation in new house. Troublesome beast from beginning but that history. Serviced by authorised Vaillant engineer late summer 2004. Since early December has non-ignition fault - no fire up with F21...