Don't know what that means , but everything old. When I first started it the pilot light would not stay lite. I brushed with a wire brush and used the vaccum on it to clean. Now carbon monoxide sensor goes off
Thanks guys! Got in there and it was dirty as hell. Cleaned it up and gently cleaned the sensor. Heats working like it did before. If it does it again I'll give someone a call but it seems good for now.