A boiler fan is a crucial component in your central heating system that plays a vital role in ensuring the proper functioning of the boiler. It is designed to create airflow and maintain pressure within the combustion chamber; the fan provides an essential combustion air supply for efficient fuel burning.
So, if your boiler fan is not working due to which your boiler is making noises or your boiler has locked itself, then in this blog, I am going to tell you how a boiler fan operates, its importance as a safety mechanism, and the common boiler fan faults that arise with your boiler’s fan, along with the solutions.
How Does a Boiler Fan Work?
The fan works by drawing in fresh air and expelling waste gases produced during combustion through a flue pipe, facilitating clean and controlled burning processes.
Equipped with an electric motor or powered by steam, the fan delivers the necessary oxygen to mix with the fuel, resulting in complete combustion while minimising harmful emissions.
It also aids in the removal of flue gases, preventing accumulation within the boiler system that could hinder performance or pose safety risks.
Moreover, some boiler fans are specifically designed to handle increased pressure requirements for industrial boilers, enabling efficient operations on a larger scale.
Importance of the Boiler Fan in Boiler Operation
The boiler fan’s primary function is to provide combustion air to the system by delivering the necessary oxygen for efficient fuel combustion. By regulating airflow, it ensures optimum combustion and helps maintain consistent burner flame stability.
An effective boiler fan also aids in removing flue gases from the combustion chamber, preventing any accumulation that could hinder heat exchange and impede overall efficiency.
Furthermore, the fan assists in maintaining proper furnace pressure by controlling the exhaust gas flow rate, thereby preventing any potential disruptions to the air-to-fuel ratio, and minimising fuel waste.
How Long Does a Boiler Fan Last?
The lifespan of boiler fans can vary depending on several factors, including the quality of the fan itself, the environment in which it operates, and the level of maintenance and care provided.
Generally, well-built, and properly maintained boiler fans can last 5 to 10 years. Let’s say your boiler is 5-8 years old and is getting faulty. Then, the problem might lie within the fan. But if your boiler has been relatively new for 3–4 years, the fault might be elsewhere rather than the fan.
However, it is essential to note that certain elements can significantly impact their longevity. For instance, excessive dirt or debris accumulation within the fan blades or the motor could cause premature wear and tear, potentially reducing its lifespan. Similarly, exposure to extreme temperatures or corrosive substances may also hasten deterioration.
To maximise the lifespan of boiler fans, proactive maintenance practices such as regular cleaning, lubrication checks, and inspections should be implemented. Investing in high-quality fans with durable construction materials will undoubtedly contribute to their extended service life.
Importance of the Boiler Fan as a Safety Mechanism
The boiler fan serves as a crucial safety mechanism within your boiler system. When you initiate the boiler, the Printed Circuit Board (PCB) communicates with the fan through an air pressure switch to verify its functionality.
If the PCB fails to receive a signal, it will prevent the boiler from starting and display an error or fault code on the screen. The system will automatically lock itself down if any issues arise with the boiler fan. In such cases, it is imperative to promptly engage the services of a Gas Safe engineer who will thoroughly examine and resolve the problem.
Does a Faulty Boiler Fan Pose Any Risks?
A faulty boiler fan does not necessarily pose any risk, as it typically starts before the rest of the machine. If the printed circuit board (PCB) does not receive any signals from the fan, the boiler will automatically lock itself out and display an error code.
However, if the boiler has already started and the fan becomes faulty during operation, it can potentially lead to the risk of carbon monoxide poisoning and even a house fire. Therefore, taking precautionary measures by installing a carbon monoxide detector to prevent these potential dangers is crucial.
Causes and Symptoms of Boiler Fan Problems
1. Faults in the circuit board
A fault within your boiler’s PCB might send incorrect signals to various components, including the fan. Also, a faulty PCB may cause your boiler not to fire up. So, if your boiler displays a fan fault code, then you should immediately contact a Gas Safe Engineer.
To determine whether the problem lies within your PCB or the fan, contact a Gas Safe engineer first and ask him to inspect the PCB with a multi-meter, as there is a possibility that the problem might not be that big and can be related to just some loose wiring connections.
And if there is no problem with the wiring, you might have to replace the whole PCB. However, if your boiler is too old, you should look to replace it with a new one, as replacing a PCB is very costly.
2. Faults with the air pressure switch
As mentioned above, when you start the boiler, the PCB sends signals to the fan through an air pressure switch. So, if the air pressure switch malfunctions, the boiler won’t start and will not receive the correct signal regarding the fan working correctly.
Contact a Gas Safe engineer to inspect the problem, and if he determines that there are no other issues and the problem is only with the air pressure switch, you can replace the button with a new one.
3. Blockage in the condensate pipe
In the winter, one common problem many people face regarding their boiler is a frozen condensate pipe. When the condensate pipe freezes, fluctuations in air pressure will occur, resulting in your boiler indicating various fan problems and displaying error codes on the screen.
To solve the issue of a frozen condensate pipe, you will need to thaw the pipe by pouring hot water on it. After that, you will need to insulate it to prevent it from freezing in the future. It is recommended that you get some assistance from a certified professional for insulation.
4. Leakage issues within the boiler
As time passes, leakage issues arise with your boiler. These leakages can cause long-term damage to various components of your boiler, including the fan.
The leakage issue should always be left to a certified professional. He will inspect the leak’s source and determine the damaged parts that need to be replaced, which might include the fan.
5. The fan speed is getting low
If the fan speed of your boiler is low, it can lead to various issues, such as the pilot light extinguishing or the boiler becoming completely locked out. These problems can arise due to inadequate airflow within the system.
To solve the low-speed issue, you must increase the fan speed to a suitable level. And for that, you will have to contact a Gas Safety Engineer.
6. Loose connections
Loose connections are caused in your boiler when the fan operates and produces small vibrations. Due to these vibrations, connections and wiring can get loose over time, causing your boiler to make strange noises.
Apart from the boiler fan noise, the loose connection between your PCB and fan can cause the PCB to send incorrect signals and lock your boiler.
Only a Gas Safe-registered engineer should deal with a loose connection because it is an internal issue. The engineer will visit your home, inspect your boiler, take off the casing, inspect the connection issues within your boiler, and solve the boiler noise issue.
Boiler Fan Replacement Cost
If you have identified the faults mentioned above and concluded that your boiler’s fan is defective and requires replacement, you may wonder about the expected cost.
The price will vary depending on the type of boiler and its size. It could be as low as £100 or exceed £200. E.g., let’s say the price of a Worcester Junior 28I boiler fan replacement is less than £100, and on the other hand, the Baxi Solo 3 boiler fan replacement cost is nearly £200.
However, to provide a fair estimate, anticipate the boiler fan replacement cost to range between £200 and £300, including parts and installation expenses.
Boiler Fan Repair Cost
The repair cost of a boiler fan is like the cost of its replacement due to the labour fees included. That’s why it is suggested that if the repair is not simple and complex, investing in a new boiler fan will be wise.
Standard Boiler Fan Fault Codes
For your assistance, below are some common boiler error codes from leading manufacturers that indicate a fault with your boiler fan:
Viessmann: 04, 05, 06, 08, 0A
Vokera—A03, 03, and E030
Worcester Bosch: C6, C6 215, C7 214, C7 217, and C1 264
Glow Worm—F2, F3
After reading this article, I hope you now know why the fan fault on your boiler fan is not working correctly. If there are other issues with your boiler, i.e., a faulty gas valve or problems with the central heating pump, please get in touch with us at 0345 3192 247. One of our on-call representatives will assist you with your situation and arrange an appointment with a Gas Safe Engineer.