If you notice that some rooms are chilly while others are warm, something may be wrong. This can be caused by blocked ducts or leaky ductwork.
Banging, whistling, and rattling noises can indicate issues with heating parts, ductwork, or debris.
An insufficient heating system consumes more energy than necessary, usually caused by clogged filters and dirty parts.
Unpleasant smell from your heating system can be caused by mold or mildew and dirty malfunctioning components.