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The Right HVAC Unit for Your Home

A couple of months ago, the HVAC unit in my home started malfunctioning. The temperature inside my home soared to over eighty degrees Fahrenheit, even though my air conditioning system ran nonstop. After inspecting my air conditioning unit, my knowledgeable HVAC contractor recommended I purchase a new system. He discussed the pros and cons of installing different sizes of HVAC units with me. After considering my HVAC contractor’s advice, I decided to purchase a three and a half ton HVAC unit. Shortly after my HVAC contractor installed my new air conditioning unit, my house started feeling more comfortable. On this blog, I hope you will discover how an HVAC contractor can help you select the right air conditioning unit for your home. Enjoy!


The Right HVAC Unit for Your Home

How To Replace The Clogged Spray Nozzle On Your Oil Boiler

by Jamie Shaw

Oil boiler systems are common in extremely cold areas of the country and where natural gas lines are not available. If you have one of these systems, then you will hear some rumbling as the boiler first fires. The rumbling is the sound of the fuel igniting to create heat. If the rumbling seems more like a loud roar or a boom that shakes your home, then your boiler has a problem that needs to be repaired. The noises and vibrations are likely to be seen with a puff of smoke. These are signs that the spray nozzle in your boiler is clogged and needs to be replaced. Keep reading to learn what the nozzle is, how a clog forms, and how to replace the nozzle. 

What Is The Spray Nozzle And How Does A Clog Form?

The oil boiler spray nozzle or burner nozzle is the small end that is connected to the main oil supply line. A fuel pump forces the oil out through a hole in this nozzle. The nozzle sits just behind the door of the furnace and sprays oil into the open combustion chamber. This creates a sort of aerosol as the fuel mixes with air. Once the aerosol is created, electrodes that sit just on top of the nozzle create a spark. This starts the fuel on fire, and a rumble is heard as this happens. 

The filters that are attached to your oil boiler may not remove all of the contaminants and solidified wax from the fuel oil. The contaminants sometimes make their way to the end of the nozzle. This can cause the end to clog. The small opening on the nozzle can sometimes warp as well as it is exposed to high levels of heat. If the end is not open enough, oil will not spray. It will drip into the combustion chamber instead. An aerosol will not be created and there will be a delay between the time that the electrodes spark and the oil ignites. When it does ignite, it will do so violently. This will create some smoke and a booming noise. This is similar to an open can of gasoline or another type of pooled fuel starting on fire. 

How Do You Find A Replacement Nozzle?

Changing the spray nozzle on an oil furnace is not a difficult job. You will need to make sure that you purchase the correct replacement nozzle, though. Nozzles will have different specifications  that must meet the needs of your boiler system. The nozzle specifications will often be imprinted on the nozzle itself. You should inspect the nozzle for numbers and letters. 

Use a socket wrench to remove the attachments from the exterior door that provides access to the combustion chamber. Gently unplug the wiring harness from the top of the fuel pump and open the door. 

The spray nozzle will be the bronze attachment on the back of the door. Look on the side of the nozzle head or shaft for markings. You are likely to see a .85 or .9. This indicates the gallons per minute of oil released from the nozzle. You should also see another number with a degree symbol after it. This tells you the angle of the oil spray, and 60 and 80 degree spray angles are common. The spray angle will be followed by a letter, and this letter indicates the type of nozzle. Most nozzles are hollow, and an A, C, H, or NS will indicate this. 

If you cannot find any markings on the nozzle, then look in the manual for your furnace to find out what you need. You can also call the boiler manufacturer with the model number of your heater to inquire about the correct sprayer.

How Is The Nozzle Replaced?

Once you have the correct nozzle, you can remove the old spray attachment and secure the new one in place. Spray nozzles twist into place and they secure to a threaded fitting that sits on the end of the oil line. The nozzle can be twisted off, but you need to make sure that you do not twist the electrodes and the bracket that helps the electrodes sit in place above the nozzle. You will need to hold the fitting while you twist off the nozzle. Use a pair of needle nose pliers to hold the attachment behind the nozzle. Use a wrench to turn the spray end counterclockwise to release it. When you remove the old nozzle, twist the new one into place and tighten it. 

For more tips, contact a heating and air conditioning service.