19499787 said:according to the paperwork the boiler has been fitted with a conversion unit allowing heating oil instead of Kero to be used
There is no 'conversion unit' as such. Nozzle change, combustion head, (on certain models) pump and air resetting, are all that's req'd.
'Gas oil' can only be used on an open flue. Open flued appliances need purpose provided ventilation for correct combustion.
Does your installation meet these requirements?
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