vailliant turbo 828 boiler fault codes F1

hello
i have bought a house with a vailliant turbo boiler with no instructions !
i had a leak today with the central heating pipe so it ran out of water and a burning smell appeared around the boiler
the boiler is coming up with fault code F1 can any one please tell me what this is ? i reset it but it wont fire up just keeps going back to F1 and also can i down load the installation manual from anywhere ?

thanks for your help

mike

Check/replace the return ntc first, or the wires attached to it, although a burning smell may point to a kaput pcb.

thanks dave

the nct and wiring look ok and i suppose i cant test it? the burning smell came from the fan area that puts out the emmisions and a bit of white smoke out the flue
when i switch it on it clicks 3 times shows me a temperature and goes into F1 fault code
will i have to call out the experts?

thanks for your help
mike

It sounds as if you have done considerable damage to your boiler.

I would recommend that you get a competent CORGI to check it.

The damage may not be that bad but safety issues are involved.

Although you can measure the resistance of the NTCs, they have to track each other and they often seem to measure OK but still dont work on your model.

Tony