Apx:1:45pm noise heard from Mainshop from wash-bay Supervisor walked over to wash-bay building to confirm, at 1:54am walked over to safety department inform Safety of Hotsy chimney was blown off. I had left and was 6 miles away. Back approx 2:08pm confirmed shut down of propane, no damage to building or injuries 2:24pm called MSHA. Appears to be failed coil.