A system for detecting abnormal situations associated with a heater in a process plant receives statistical data associated with the heater unit. The statistical data is analyzed to detect whether one or more abnormal situations associated with the heater exist. The statistical data may comprise statistical data generated based on pressure variables sensed by one or more pressure sensors associated with a furnace, a stack, a fuel supply, etc., associated with the heater. Additionally, the statistical data may comprise statistical data generated based on temperature variables sensed by one or more temperature sensors associated with the furnace, the stack, etc. If an abnormal situation is detected, an indicator of the abnormal situation may be generated.