Completed a full heating system inspection and performance evaluation. The furnace is approximately 20 years old, which places it well beyond the average life expectancy of 12–15 years for most residential systems. During today’s tune-up, several concerns were identified: • Flame Sensor: Sensor was removed and cleaned due to improper microamp readings. After cleaning, readings improved slightly but are still weak and below optimal range, indicating the sensor is near failure. A weak flame sensor can cause intermittent shutdowns and nuisance lockouts. • Hot Surface Igniter: The igniter is testing below manufacturer threshold specifications. This indicates deterioration of the element, increasing the risk of a no-heat situation if it fails completely. • Burner Assembly: Burners are heavily corroded and beginning to break down. Corrosion affects flame carryover and proper combustion, which can lead to delayed ignition and unsafe operating conditions. • Debris in Burner Tubing: Excess