When something goes wrong with your furnace that causes it to trip a breaker in the electrical panel, your furnace won't run until the problem is fixed. The first step is to figure out what caused the breaker to trip. Here are some things you can do yourself to fix and prevent the problem and when you need to call a professional for repairs.
Check the Filter
If there is no power to your furnace but the rest of your appliances and lights work, then that's a good sign that the breaker flipped off in the electrical panel. Check the panel to see if that's the case. Before you flip the breaker to the on position again, look at your furnace filter and see if it is clogged with dust and needs to be replaced. A clogged filter limits airflow into the furnace and that can cause the blower to strain, overheat, and trip a circuit. Simply replacing the filter might help. Once you've changed the filter, flip the breaker back on and see what happens. If the circuit shuts back off, then you'll need to call a professional to figure out what's causing the furnace to shut down.
Let a Professional Look at the Problem
Other things can cause the blower to overwork and flip off the breaker. If the furnace has to run continuously to reach the set point on the thermostat, it might overheat and shut down the breaker. This could happen if air is leaking out of the ducts because a raccoon tore them open or because a window is broken and lets cold air in the house. Blocked registers could also cause the blower to work too hard, or there could be problems with the blower motor. Once the cause is pinpointed, a technician can make the necessary furnace repairs. This could involve repairing worn parts or cleaning the blower to get rid of dust accumulation.
Prevent the Problem from Happening Again
There are a few things you can do to protect the blower in your furnace and keep this from happening. While parts can wear down due to age, problems with the blower often happen due to things that could have been prevented. Always change your filter on schedule so dust won't restrict airflow or get pulled into the blower. Also, remember to schedule an annual service call for your furnace that includes cleaning it to get rid of dust and grime on the blower. In addition, if you notice your furnace is running longer than usual and it's still not warm in your house, then check all your registers to make sure they aren't blocked and look at your ducts if possible so you can tape up gaps caused by pest damage.