The answer to 'when to service furnace repair' is that your furnace should be serviced annually, ideally before the start of the heating season. Regular maintenance is essential to ensure your furnace is running safely and efficiently, and can help prevent costly breakdowns during the winter months.
During a furnace tune-up, an HVAC technician will inspect the various components, clean the system, check for any wear or damage, and make necessary adjustments. This helps improve the furnace's performance, extend its lifespan, and identify any potential issues before they become major problems.