Responded to no-heat call for 4-year-old system. Diagnosed exhaust pipe blockage on roof that had frozen over, requiring removal of T-fitting to clear obstruction. Upon roof inspection, discovered excessive pipe movement which led to attic investigation where a disconnected exhaust elbow was found venting combustion gases into attic space. Repaired and secured the disconnected elbow joint with appropriate adhesive to restore safe operation. Noted lack of insulation on all attic exhaust piping, which likely contributed to condensation freezing. Recommended insulation installation for all exhaust runs to prevent future blockages.
