Fireplaces are nice to have on a cold winter day, and having a fireplace insert keeps the logs in place and looks great too. But if your fireplace insert is rusting, the aesthetics come into question. Stopping the rust quickly is the best thing to do, and it can be done with a little bit of prep in just an afternoon.
Rub the red scuff pad over the rusted area, this will remove most of the loose rust off of the fireplace insert.
Scrub the surface with the wire brush which will remove most of the stubborn, stuck on rust. This is going to clean up the area and remove the damaged metal.
Clean the fireplace insert using the lint-free towels and the cleaner/degreaser. This may take some time as there is most likely some ash on the fireplace insert.
Apply the high-temp spray paint to the surface. This will protect the paint from rusting further, but will still function when exposed to open flame.
Allow the insert to dry for at least 24 hours before placing the insert back in the fireplace.