Most furnace failures are the ignitor, the flame sensor, or a safety switch doing its job. The heat exchanger is the expensive one and it is a safety issue rather than a comfort one.

Change the filter first – restricted airflow trips the limit switch and mimics a failed furnace. If the unit lights then shuts off within a minute, that is usually the flame sensor and it can be cleaned. Rust or soot at the exchanger means stop using it and get it inspected.

Oklahoma city pages

• Bartlesville
• Broken Arrow
• Edmond
• Enid
• Lawton
• Moore
• Muskogee
• Norman

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Written by Jaylan Jones. Sooner Home Services earns a referral fee when a call connects to a contractor. See our business-model disclosure.