Replacing Riello Burner Fuel Nozzle: Step-By-Step Guide

Changing the fuel nozzle on a Riello burner is a delicate operation that requires careful attention to detail. While it may be tempting to attempt this task as a DIY project, it is important to recognise when professional help is needed to ensure safety and avoid costly mistakes. This guide will outline the steps involved in changing the fuel nozzle on a Riello burner, including important considerations for specific models such as the Riello 40 Series and the F3. By following these instructions, homeowners can gain a better understanding of their heating system and make more informed decisions about its maintenance.

Removing the burner and blast tube

To remove the burner and blast tube, start by switching off the power to your Riello burner. Next, remove the burner from the boiler. Once the burner is out, you will see a cylindrical tube, known as the blast tube, housing the burner nozzle.

The blast tube is usually held in place by a couple of screws. For the Riello 40 burner, these are Phillips screws, while for other models, they may be Allen key screws. Be sure to use the correct type of screwdriver to avoid damaging the screw heads. With the screws removed, carefully pull off the blast tube to expose the nozzle.

The nozzle will be hexagonal in shape and brass-coloured (unless it is very dirty). It has a hole in the middle. Now, simply undo the nozzle with a spanner and replace it with a new one of the same size. It is important to note that simply cleaning out the boiler is not the same as servicing it. A full combustion test is also recommended, especially if you are changing the nozzle size, as the boiler settings will need to be adjusted accordingly.

Identifying the nozzle

Locate the Blast Tube: The first step in identifying the nozzle is to locate the blast tube, which houses the burner nozzle. It is a cylindrical tube that is usually held in place by a couple of screws. These screws can be either Allen key screws or Philips screws, depending on the specific model of the Riello burner.

Remove the Blast Tube: Once you have located the blast tube, proceed to remove it by unscrewing the screws. Be careful not to use the wrong type of screwdriver, as this can damage the screws and make them difficult to remove. For example, when dealing with Philips screws, avoid using a Posidriv screwdriver.

Access the Nozzle: With the blast tube removed, you will now have access to the burner nozzle. The nozzle is typically hexagonal in shape and brass-coloured, although it may appear black due to soot or residue buildup. It has a hole in the middle, and you will need a spanner to undo it.

Take Note of Nozzle Specifications: Before removing the nozzle, take note of its size and any markings or specifications on it. This information will be crucial when it comes to replacing the nozzle with a new one. Ensure that you replace it with a nozzle of the same size and specifications to avoid any compatibility issues.

Consult Manual or Expert Advice: If you are unsure about the nozzle size or specifications, consult the burner's manual or seek advice from a qualified technician. It is important to have the correct information before proceeding with any changes or replacements. Additionally, keep in mind that simply cleaning out the boiler is not the same as servicing it. A full combustion test is recommended, especially if you are changing the nozzle size, as boiler settings may need adjustments.

By following these steps, you can accurately identify the fuel nozzle on your Riello burner, ensuring that you have the necessary information for any maintenance or replacement work. Remember to exercise caution and refer to the appropriate resources if you have any doubts during the process.

Unfastening the nozzle

To begin the process of changing the fuel nozzle on a Riello burner, you must first remove the burner from the boiler and switch off the power. This will ensure a safe working environment. Next, locate the blast tube, which is a cylindrical tube housing the burner nozzle. The blast tube is usually secured with a couple of Allen key screws or, in some cases, two Philips head screws. Using the appropriate screwdriver, carefully remove these screws.

Once the blast tube is removed, you will be able to see the fuel nozzle. It will have a hexagonal shape and a brass colour (unless it is too blackened with use). At this point, you can proceed to unfasten the nozzle. Place a 16 mm spanner on the nozzle and a 17 mm spanner on the nozzle holder. Gently loosen the nozzle by turning the spanner in the appropriate direction. Remember to read the information on the nozzle or take it with you when purchasing a replacement.

It is important to note that simply cleaning out the boiler is not the same as servicing it. A full combustion test is recommended, especially if you are changing the nozzle size, as the boiler settings will need to be adjusted accordingly. Additionally, ensure that you replace the nozzle with one of the exact same size to avoid any compatibility issues.

Replacing the nozzle

Before starting, ensure you have the right tools for the job. You will need an Allen key, a spanner, and a screwdriver. It is also important to note that you should replace the nozzle with a new one of the same size.

First, remove the burner from the boiler and switch off the power. Next, remove the blast tube by unscrewing the two screws. These are usually Allen key screws, but they can also be Philips screws. Do not use a Posidriv screwdriver as you will not be able to easily remove the screws if you round the heads. Once the blast tube is removed, you will see the nozzle.

The nozzle is hexagonal in shape and brass-coloured (unless it is too blackened). It has a hole in the middle. Simply undo it with a spanner and replace it with the new nozzle of the same size. Be sure to hold the nozzle holder with a 17 mm spanner while undoing the nozzle.

After replacing the nozzle, do not forget to perform a full combustion test on the boiler, especially if you have changed the nozzle size as the boiler settings will change too.

Testing the boiler

Once you have replaced the fuel nozzle on your Riello burner, you will need to test the boiler to ensure it is working correctly. Here is a step-by-step guide to testing your boiler:

Step 1: Check the Blast Tube

Before turning on the boiler, it is important to ensure that the blast tube is securely attached. Check that the screws you loosened when removing the blast tube are tightened, and the tube is firmly in place. Make sure you used the correct type of screwdriver for the screws, as using the wrong type can damage the screw heads.

Step 2: Initial Test

After ensuring the blast tube is secure, you can turn on the boiler and run an initial test. This will involve igniting the boiler and checking that it is functioning as expected. Observe the flame and ensure it is stable and burning cleanly without any signs of smoke or sooting.

Step 3: Check for Leaks

After the initial test, turn off the boiler and check for any signs of oil leaks. Inspect the area around the nozzle, blast tube, and any seals or gaskets for oil residue or drips. If you notice any leaks, tighten the connections and ensure that all seals are intact.

Step 4: Combustion Test

Perform a combustion test to ensure the boiler is burning fuel efficiently and safely. This will involve measuring key parameters such as carbon dioxide (CO2), carbon monoxide (CO), and oxygen (O2) levels in the flue gas. You will need a combustion analyser to perform these measurements. Compare the results to the manufacturer's specifications to ensure they are within acceptable limits. Adjust the boiler settings if necessary, following the manufacturer's instructions.

Step 5: Observe Boiler Operation

Run the boiler for an extended period and observe its operation. Check for any unusual noises, vibrations, or smells. Ensure that the boiler is heating the water to the desired temperature and that the heat output meets your expectations. Observe the flame periodically to ensure it remains stable and clean-burning.

Step 6: Safety Checks

Finally, perform some safety checks to ensure the boiler is operating within safe parameters. Check the boiler's pressure and temperature gauges to ensure they are within the normal operating range. Inspect the boiler for any signs of corrosion or damage, and ensure that all safety devices, such as the pressure relief valve, are functioning correctly.

Remember, if you are uncomfortable or unfamiliar with any of these procedures, it is best to consult a qualified technician to perform the testing and ensure your boiler is safe to operate.

Frequently asked questions