How to Clean the Furnace’s Burners

How to Clean the Furnace’s Burners 

A furnace burner is a part of the furnace where fuel and air are mixed and burned to produce heat. Pipes or ventilation systems are used to spread the warm air throughout the house. A pre-mixer may also be included in a furnace burner. Before the burner, there is an area where the air and fuel are blended. This improves the furnace’s efficiency and ensures a more efficient combustion process.

A big part of furnace maintenance is cleaning. The in-shot type of burner is more common and easy to get. Depending on the furnace model, they differ by the manufacturer which might be a little more difficult to clean or to get to the burners.

Some furnaces have a panel covering the burners and you’d have to remove that access panel. You might have to remove the bracket holding the burners in place in some furnaces. You might have to loosen the screws holding the gas supply in place.

Whatever your furnace is configured, be mindful of how things come apart, so you can put it back together when you’re done. If you’re uncomfortable doing stuff like this and you’re, not sure which screws to remove then don’t mess with it and leave it to the experts.

When you have your furnace serviced each year, your technician should inspect the burners and let you know if your furnace needs some extra attention.

1. Turn Off the Furnace (Switch and Gas Line)

Since you are going to be working on gas components, you will need to shut off the power and the gas. To shut off the gas, search for the hard pipe (gas line) outside of the furnace, it should be pretty close.

Follow it down and make sure it goes into the furnace to confirm it is the gas line and then follow it back out until you come to a valve. It might look different in each home but it is easy to find and identify. Turn the valve until it’s perpendicular crossways to the valve body.

2. Remove Furnace Door

After making sure the furnace is off. It means opening and touching anything inside is safe. Take the doors off the furnace. This is going to expose the burner assembly.

You will see the gas valve and then the pipe that flows around the burner. The gas travels through this pipe and then on the other side of the pipe are the orifices. The orifices or gas orifice jets are where the gas is being pushed through.

The burners have an opening on the rear part and they sit over the has orifice jets. The gas goes through and they’re ignited and they burn into flames.

It is important to figure out how to get the burners out without having to take everything apart. There will be some screws holding the burner in place which are hard to reach.

In this case, you can use a flexible angle extension tool to reach the screws inside. But in case it won’t fit, you will need to give yourself more room. This means you will need to take the top plate off.

There will be screws holding the top plate in place. You can remove the plate and then maybe have enough room for your extension.

3. Inspect the Burners Using a Mirror

Before you actually dismantle, you must first inspect the burners. You can use an inspection mirror or any mirror to give you visuals of the burners. The purpose of this is you may not have to clean the burners at all.

Stick your mirror back there and see the front side of the burner. This is what a technician would normally do. They would inspect the burners to see if they’re dirty, looking for signs of dirt, dust, rust or build-up on those burners.

In some circumstances, you may not even need to pull out the burners and clean them. How dirty the burners can get depend on the conditions the furnace is installed in.

Some of them are installed in attics, crawl spaces, laundry rooms and anything in the air, any of the dirt, dust, lint, these stuff gets pulled into the furnace and can collect on the components inside.

4. Take Photos as Reference

If in case there is a need to take off the burners for cleaning, before you start taking things apart, take a minute and look at how these things are put together.

It’s not a bad idea to take a picture you can refer back to if you do have to disconnect wires and other things to get to the burners. Be sure you know where you’re disconnecting the wires from so you can put them back the way you found them.

When taking out the top plate, you will see the igniter attached to it. It is a thin rod and it is most likely had become brittle because of the continuous process furnace heats up and cools down. So, you want to be careful when you’re dealing with it and parts near it.  Whenever you’re pulling it out, make sure not to break it.

5. Removing the Burners

Once you have enough space, take off the screws holding the burners. With your hand under the burners, push up the burner so it detaches from whatever it’s holding on to. Then using your other hand, push the burner away from the pipe, because it’s sitting over the top of that gas orifice.

Burners come out individually but other burners may come out as a solid piece or they could be interlocked together.

It is important to keep track, of which side is up and which side is down when you take the burners off. It might not seem like it makes a big difference and there are furnaces it might not need to, but there are furnaces that it does.

So, just make sure you know which way is up and down.

6. Cleaning the Burners

To clean the burners, the owner’s manual might not give you specific instructions on how to clean them. There are a couple of different ways to clean them. If you look on the backside of the burners, there are a couple of places which are important to make sure are clean.

Check the burner’s face and look for a buildup of dirt, dust, and rust. But then you also have the little channels or holes. Make sure those don’t have anything stuck inside.

If there is dirt on the surface you can easily brush off, you can use a brass brush. The brass brushes are commonly used in cleaning the burners. you can sit there and clean those.

For burners which have a lot of buildup or dirt, the other option to clean is to take some soapy water and rinse them out in the sink.

Use warm water and you don’t have to use a ton of soap. If the buildup on your burners is more stubborn, you can use a toothbrush to scrub a little bit. Just make sure you rinse all the soap and then dry them before you reinstall them back on your furnace.

Letting your burners dry could take time so you can use an air compressor to blow them dry. If you’ve got some compressed air, you could use it or shake them out and let your burners sit for a little bit.

7. Check the Orifices

Before you put the burners back in the furnace, you might want to check the orifices on the other side of this gas line while your burners are not installed back yet. Just use the inspection mirror and see if there are any obvious blockages.

You might want to take this chance as well to clean your orifices jets and also some other components of your furnace. You can use a brush and clear any blockages.

8. Place the Burners Back Together

Then put the burners back together with the way you took them apart, tighten the screws, reassemble everything. Be sure you hook the wires back up if you have disconnected any and connect them back the way you disconnected them.

Always check and compare with your reference photo.

Then turn the gas back on, turn the power back on. Make sure it is working and you didn’t accidentally miss something. Once you are done, put the door back to close your furnace.

This is not necessarily a beginner project so if you are not comfortable doing this kind of stuff on your furnace, please don’t do it and instead ask for professional help.

If you have your furnace serviced each year, you should have it inspected (the technicians should inspect the burners and they will let you know if they need to be cleaned).

If you found this article helpful, check out the other articles and again remember, if you ever feel like you got in over your head, stop and call a technician. Your safety is still your priority.