When you call an HVAC technician to help you with a heating problem, you usually want them to get in, find the issue, and solve it as quickly as possible. Unfortunately, furnaces are relatively sophisticated systems, and there's plenty that can go wrong. Without good information, diagnosing a problem can sometimes take longer than repairing the actual fault.

While you should leave the most significant repairs to a trained professional, there are a few things you can do to help your technician get their job done more quickly and efficiently. These three tips will help you diagnose some common furnace problems so you can provide your tech with a more thorough and valuable description of your issue.

1. Check for Airflow Issues

Your furnace needs to breathe, and it will quickly overheat if there's insufficient airflow through your home's ductwork. Typical sources for airflow issues include clogged filters and blocked return ducts. Before making a call to your local heating repair specialist, check that your filter is in good shape and that your vents are clear.

Even a seemingly minor airflow restriction can cause your furnace to overheat and shut down, so it's always worth checking these items to avoid an unnecessary service call. Letting your technician know that you already checked these two items also helps them narrow down the problem to other potential sources.

2. Confirm Your Furnace Turns On

Your furnace only turns on when a thermostat calls for heat. To confirm that this is working as it should, try increasing the temperature on one of your thermostats. You don't need to raise it too high, but you should set it at least several degrees above the ambient temperature. The thermostat should start calling for heat quickly, and your furnace should turn on.

If you can, listen near your furnace. You should hear the sound of the inducer fan turning on when your thermostat calls for heat, followed by the sound of the burners igniting and the house blower turning on. Let your technician know if your furnace doesn't turn on or if you don't hear the burners igniting or the house fan turning on.

3. Look at the Flames

Many furnaces contain a sight glass that allows you to view the flames. You can also remove the furnace cover to watch the burners, although you should only do this if you're comfortable with a bit of disassembly. The flames should be blue, steady, and contained. If the flames appear to waver, have a yellow or orange tint, or roll out of the combustion chamber, you may have a severe problem.

If you notice any of these issues, it's a good idea to stop using your furnace since you may have a rollout problem or even a damaged heat exchanger. Contact a professional as soon as possible to investigate and repair the issue.

For more information on heater repair, contact a professional near you.