Your Guide To Furnace Troubleshooting

Before winter hits hard, you might want to consider testing your furnace to ensure it is running how it should. The last thing you want is for problems to hit when it’s too late, and the best way to find problems early is by having a professional service the heating system. Do this at least a few weeks before you expect it to be needed daily, and you won’t be left in the cold.

If you wanted to test the furnace yourself there are a number of things you can look for to know whether there are issues.

By understanding some of the most common furnace problems, you can be proactive and sort them out before it ends up costing a fortune.


Dirty filters: Dirty air filters will reduce your system’s airflow, which will run the furnace I overtime chewing up energy. Clogged filters can also damage your furnace’s limit switch.

Lack of maintenance: If you don’t maintain your system you are asking for trouble. Routine maintenance is the best thing for your system, and can pick up minor issues before they become major, and will ensure your system runs efficiently.

Pilot control and electric ignition or problems: A faulty pilot or ignition will make it very difficult to keep your home warm. Thermocouple problems, and blockages in the system can result in a failed pilot light.

The Thermostat

Thermostat settings: When your system’s blower fan cycles too much, or does not turn off at all, it could mean there are problems with your thermostat settings. Many issues can occur with thermostats, and one of the most common is that the settings are simply wrong.

Thermostat batteries: One of the simplest to fix, but hardest to fault find, is the batteries that run your thermostat. It’s sometimes the simplest issue that causes a major problem, and this is one of the most common. Check your temperature settings are correct to your desired temperatures.

Faulty thermostat: A faulty thermostat can lead to issues with the fan and more importantly, the temperature levels.

Other Faults

Complete furnace failure: If your furnace has problems with power, gas, the thermostat setting, or the pilot light, it can completely shut the system down.

The furnace doesn’t heat efficiently: If your system is too small for the space, or has a any of a number of issues like clogged filters, it may not heat the room efficiently.

Recurrent cycling: If your system is cycling between “On” and “Off” it could mean you have a blocked filter, bad airflow or a faulty thermostat.

The blower endlessly runs: Blower issues can indicate problems with your system’s limit switch.
Noisy furnace: Most systems are quiet, so if you hear any noises coming from your system it could mean there are mechanical, airflow or burner issues.

Pilot light blows out:
If your pilot light goes out, it could be an issue with a draft in the area. You will need to assess the area and ensure no drafts can affect the pilot.

Natural gas or propane issues

If you suspect there is an issue with the gas supply, turn off your supply and contact an emergency furnace repair specialist to ensure your home is safe, and any repairs are carried out as soon as possible.

If you have issues with your furnace that you cannot find, it’s always a better option to call a professional who knows what they are doing. Routine maintenance on your heating system will prevent expensive issues occurring when you need it the most.