What Causes a Furnace to Not Ignite

There is no doubt that gas furnaces are reliable home heating appliances. Statistics show that nearly one-third of all homes in Australia are fitted with gas furnaces. They are not only eco-friendly but are also affordable, energy efficient and safe. However, just like any other appliance, gas furnaces are also prone to breakdown. Failure to ignite is a common problem that most furnaces are prone to. If your furnace is not able to ignite, then it means that you will stay in the cold until the problem is fixed. So what causes a furnace not to ignite? In this article, we are going to give you the reasons why your furnace does not ignite and possible solutions.

1. Gas supply has been cut off

The first thing that you need to do when you realize that your furnace does not ignite is to check if the gas supply is intact. You might be surprised to find out that the reason why your furnace is not igniting is that the gas supply has been cut off. If the pressure gauge indicates that the gas pressure is 25 or above, then it means that your gas supply is intact. If it is below 25, then you need to call a heater service to check and fix the problem.

2. Clogged air filters

Another possible reason why your furnace does not ignite is that the air filters are heavily clogged. Remember that gas furnace needs air in order to burn. If the air filters are clogged, then it means that that air in the furnace will not flow freely. As a result, your furnace will not ignite because it will not achieve the required air to gas ratio. To prevent this, then you need to ensure that the air filters are changed regularly (at least once a month) to ensure that air flows freely in the furnace.

3. Faulty thermostat

If air filters are in good shape, then the problem may lie on the thermostat. The thermostat plays a crucial role in regulating the temperature in your home. In fact, most heater repair experts say that the best way to know if you have a faulty thermostat is to check if the furnace is igniting or not. The furnace can only ignite if there is good communication between the thermostat and the igniter. Check the thermostat to see if it is faulty or it is not set correctly. If that is the case, then you need to call an experienced heater service provider to replace or set the thermostat correctly.

4. The igniter has burnt out

Just like any other component of the furnace, igniter also burns out with time. If your furnace is not able to ignite, then it is probably because the igniter is too old. Check the igniter to see if it glows when you turn it on. If it does not glow, then it means it has a problem. The good thing is that this problem can be fixed easily by a heater repair expert. There are two types of furnace igniters. They include pilot light igniter and electronic furnace ignition. The heater repair expert will carefully inspect your furnace ignition and replace the faulty one with a new one.