Hi does anyone know if its possible to run my Oil Boiler on Red Diesel??

You need to Change the jets

The geezer that bought my boiler bought it as he had been burning red and it sooted up – kerosene burns much cleaner than derv

It maybe. Depends how old it is and how it is flued.
Usually as trail rat says nozzles and alter pump pressure.
Not sure why you would want to though as you probably will need two services per year

got an endless suply o red lol

got an endless suply o red lol

That sounds dodgy!! Is there much difference in price these days? Unless you will never see the bill might be easier to clean the tank out and fill with oil

Reds about 20 p dearer