Russell Comfort Solutions

Why Is My Furnace Not Heating? 8 Common Causes

When your furnace stops heating during a Denver winter, it's more than an inconvenience — it's an emergency. Here are the 8 most common reasons.

8 Common Causes

  1. Thermostat Issues — Check batteries and settings.
  2. Dirty Air Filter — Restricts airflow, causes overheating shutdown.
  3. Pilot Light or Ignitor Failure — Common and affordable repair.
  4. Gas Supply Issues — Check gas valve and other appliances.
  5. Blower Motor Problems — Can't push heated air through ducts.
  6. Heat Exchanger Cracks — Safety hazard (carbon monoxide risk).
  7. Flame Sensor Issues — Furnace ignites briefly then shuts down.
  8. Altitude-Related Issues — Denver's 5,280 ft affects combustion.

Call (720) 302-3513 for same-day furnace repair.

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