The answer to 'why is my smoke detector burning smell' is that a burning or acrid smell coming from your smoke detector is typically a sign of an electrical issue or overheating. This could be caused by a faulty component, a loose connection, or the detector simply reaching the end of its lifespan.
Some common causes include a malfunctioning circuit board, a worn-out battery, or dust buildup inside the detector. The smell may also indicate that the smoke detector is overheating and could potentially catch fire if not addressed promptly.