Question about my gas boiler..?

make sure you secure it back in place, just pushing it in may not be enough, you may be able to screw it in with very small screws. if the pipe is plastic you will need to glue it in with the proper glue. don't take a chance, carbon monoxide is very dangerous and could be building up in your attic, it won't come down, because its a lighter gas but can aculate to dangerous levels.Call a pro if your unsure.