Can I light my fire which has a back boiler but now has oil central heating. If not disconnected is it safe?

I've been told my house can blow up if not disconnected properly! How can I tell whether it's safe or not?Can I light my fire which has a back boiler but now has oil central heating. If not disconnected is it safe?
If you have a proper expansion tank on the system, a proper blow-off valve (Temperature/Pressure Relief Valve), and the means to run the circulator, you will be fine. Most systems that utilize separate water heating sources have a manual circulator switch for this purpose, or have a thermostatically operated 'smart-box' that will run the circulator but not turn on the oil burner based on how it is set.





What you do not want to do is have the back-boiler heat-exchanger valved off from the main system. What will happen in this case is that the water in the exchanger will boil and possibly cause the pipes to burst if the proper relief is not provided. If you are not sure, have the heating professional that set up the new boiler check (and install) the correct controls and make sure that the proper safety devices are in place and operational - then you need to understand how they work and how to operate them safely. It is just another layer of knowledge you will need to have if you wish to have a 'dual-fuel' system.