The answer to 'furnace short cycling' is that short cycling, where the furnace turns on and off rapidly, is a common issue that can have several underlying causes. This can be a symptom of a problem with the furnace itself or the thermostat, and it's important to diagnose and address the root cause to prevent further damage and inefficiency.
Some common causes of furnace short cycling include a malfunctioning thermostat, clogged air filters, issues with the blower motor or fan, or problems with the furnace's heat exchanger. Symptoms may include the furnace turning on and off frequently, inconsistent heating, and higher energy bills. While some simple troubleshooting and maintenance can be done DIY, it's often best to call a professional HVAC technician to properly diagnose and fix the issue to ensure safe and efficient operation of your furnace.