How to change the nozzle, pump screen, and oil filter on your oil-fired heater. Make sure if you’re replacing the nozzle you get the right one for your heater. They must make about a hundred different ones. Very important that you do use the right one.
How a nozzle works
They produce a uniform spray of fuel into the heater box. They come in different flow rates and spray degrees so make sure you get the right one for your heater. Even a wrong will work, but it could end up costing you a lot more in fuel.
I m changing the nozzle is there a chance of back draft
I’ve never heard or had a issue with back draft being an issue from changing the nozzle. But do make sure you install the correct one.