Furnace runs but some rooms are too cold while others are too warm

Safety: Ensure registers and returns are not blocked by flammable materials.

• 1. Filter: Replace the furnace filter to ensure proper airflow.
• 2. Register adjustment: Slightly close registers in overheated rooms and fully open registers in cold rooms to balance airflow.
• 3. Return air: Make sure return grilles are not blocked by furniture or drapes.
• 4. Professional duct assessment: If issues persist, have a technician evaluate duct sizing and layout.