Repairing HVAC equipment is never cheap, but dealing with a gas furnace can be particularly expensive. Natural gas is dangerous, and working with natural gas appliances requires training, experience, and often special licensing. As a result, fixing the problems that can occur on an aging gas furnace isn't a job for the typical home do-it-yourselfer.

However, not every furnace repair needs to be a bank-busting event. You can often avoid more expensive repairs by noticing problems sooner and addressing them before they become critical. Learning about these three expensive furnace repairs can help you understand why they cost so much and how you ensure they don't happen to your home's furnace.

1. Blower Motor Failure

Your furnace blower is the main fan that pushes air through your home's ductwork. Problems with your blower can limit the amount of air that can reach the rooms in your home, reducing your furnace's overall efficiency and leaving you shivering. Even worse, inadequate airflow can cause severe damage to your furnace's heat exchanger.

How You Can Avoid It: Blower motors often fail because they become overworked or because too much moisture enters the cabinet. Routine annual maintenance and regular furnace filter changes can help you avoid the former situation. While some moisture in your furnace cabinet is unavoidable, you can avoid excessive build-up by monitoring for and repairing issues with your furnace's condensate drain.

2. Draft Inducer Motor Failure

The main blower isn't the only fan in your furnace. The draft inducer creates negative pressure that draws combustion gases through the exhaust flue, ensuring safe and efficient combustion. Since this expensive part is critical for your furnace to operate safely, a failed draft inducer typically trips the furnace's pressure switch and prevents your heat from working.

How You Can Avoid It: As with main blowers, draft inducers often fail when they overheat or become overworked. Routine maintenance to ensure your furnace burns cleanly and efficiently can help extend your draft inducer's life. Additionally, never ignore problems with your exhaust flue. Exhaust flue obstructions can cause the draft inducer to work too hard, potentially shortening its lifespan.

3. Heat Exchanger Cracks

Cracks typically form in your heat exchanger when it overheats. These cracks are incredibly dangerous and can potentially allow combustion gases to escape into your home. Even worse, replacing a heat exchanger is so costly that a full furnace replacement is often a more cost-effective option.

How You Can Avoid It: The best way to extend the life of your heat exchanger and avoid cracking is by regularly changing your furnace filter. Ensuring adequate airflow will help to prevent the heat exchanger from overheating, which can create metal fatigue. Likewise, quickly addressing issues with your furnace's main blower can help to prevent airflow restrictions that may damage your heat exchanger. 

For more information about furnace repair, contact a local company.