I just bought a 10 year old oil burner from one of the busiest quick lubes in town. They have had it since they went into business a decade ago and felt like it was time to get a newer more efficient one. The owner gave me a screaming deal on it which came out to be 95% bellow market rate even for a boiler this old. I was a Buderus with a Wetzlar motor.
What Are you Going to Need to Clean Your Waste Oil Burner
You are going to need just a few things. They are the following a) masks b) chimney brushes c) broom d)shop vac (optional but nice if you have it) e) large piece of cardboard f) brake parts cleaner

Items You Will Need
Step 1- Cleaning the Oil Boiler Chamber and Door
You are going to need to lay the large piece of cardboard by the entrance of the boiler. If you do not than ash is going to get all over the place and believe me its extremely hard to clean up.

Waste Oil Burner Before Cleaning
We always like to start off with the door. These oil burner doors usually have an asbestos gasket on them so you want to use a brush with softer thistles like a broom and not the chimney brush which would be way to hard on it. Please wear a mask while doing this. Remember that this machine burns waste oil and you have no earthly idea what was actually in it.
You want to brush the door off really well. Ash is going to be flying all over the place. Inspect the opening of the chamber where the actual burner assembly goes. Look for buildup and burn marks. If there is a lot of build up than the boiler has probably not been shutting off like its supposed to.

Oil Burner Door Being Cleaned
You are then doing to want to clean the actual chamber. Again, I respect, make certain you have your mask on. Take the chimney brush and start scrapping away all the ash and debris out. This is going to take a good 20-30 minutes alone. You want to brush out as much ash and soot as you possibly can. A tenth of a millimeter of of extra ash or soot can reduce of efficiency of your oil burner by alot.
Take the shop vac at this period of time and vacuum up all the other loose dust that you missed.
The goal is really to get the chamber as clean as you can. The boiler chamber is what transfers the heat to the water and if its dirty its not going to do a good job of this.

Cleaning Oil Burner Chamber
Step 2- Cleaning the Actual Oil Boiler Assembly
Okay so here is the hard part. Up to this point we have just cleaned the chamber. Now we are actually going to clean and adjust the device that ignites that oil and produces heat.
So I like to start off with the burner gun. Its usually coasted with ash. Clean off with a brush.

Oil Burner
Continue to the flame retention head. Brush off what you can. You are going to have to use a flathead screwdriver to scrap off the excess ash.

Scraping ash from burner gun and flame retention head
Disassemble the whole assembly. You can start anywhere but you are going to have to wipe off and clean all the major components within the oil burner. You want to get them as clean as possible. You may want to start by removing the pre-eheater and shroud off.

Burner Ignitor
When you start to take the shroud off you are going to see the nozzle with the two ignitors right above it. This is the heart of the boiler. The way it works is that the waste oil comes out the nozzle mixed with air and is then ignited to produce a mass amount of heat. You can clean the ignitor and nozzle off with brake part cleaner. It usually melts the ash and soot away. Honestly there is most likely going to be a lot of grime that is going to be caked on so you are going to have to use gasoline to melt it away. You can see from the picture that we were forced to go this route.

Cleaning oil boiler with gas

Gas Melts Ash and Dirt Off Waste Oil Boiler
After you do this you can put everything back together. Your burner is now clean and ready to run. You fill find that it runs a lot more efficient and better than when its filled with dirt.
Tags: boiler chamber, burner gun, Oil Burner, waste oil boiler
Thanks for the useful info. It’s so interesting
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