Viessmann Boiler F FA Fault Code
The Viessmann fault code F FA relates to the fan and here we have Q & A or require an engineer for an emergency boiler repair.
The Viessmann Boiler Fault Code F FA Error Common Q & A
Just below, we have a list of common questions relating to the F FA fault code on the Viessmann Boiler.
- What does the F-FA fault code mean on my Viessmann boiler?
- What does the fan do on my boiler?
- Can I reset my boiler to fix the problem?
- How will my boiler engineer know if the fan is faulty?
- How much is it going to cost to replace the fan on my boiler?
- My boiler repair company thinks that the PCB is the problem, does this sound correct?
- I need to replace the PCB, how much will this cost?
- My boiler engineer thinks components have been damaged by moisture, how is this possible?
What does the F-FA fault code mean on my Viessmann boiler
If you’re having problems with your Viessmann boiler and it’s displaying the F-FA fault code, there is a problem with the fan.
The boiler has recognised that the fan is working. However, the fan hasn’t stopped running, even when the printed circuit board (PCB) gives the signal for it to do so.
Due to the nature of the fault, it’s likely that your boiler is going to lockout. That means it won’t work, and the F-FA fault code is going to be shown on the display panel.
What does the fan do on my boiler
The fan is an incredibly important component in your boiler. So important, that the boiler won’t ignite until it recognises that the fan is operational.
Modern boilers expel waste gases. And, these waste gases can be incredibly harmful.
Some of these gases are pushed out of the boiler via the condensate pipe. The others are vented out of the flue.
The fan starts up before your boiler ignites, so there’s a draught ready to push gases out of the flue. Once the air pressure switch notices a change in pressure, meaning the fan is working, the PCB gives the signal for the gas valve to open and the boiler to ignite.
However, when there’s no longer demand for heat, the burner should shut down, as should the fan. If the F-FA fault code is being displayed, the fan isn’t shutting down even though it should have. It’s likely you’ll hear the fan humming, while all other components are off.
Can I reset my boiler to fix the problem
The reset function on your Viessmann boiler isn’t designed to fix problems. So, it should only be used once a problem has been found and fixed.
In the case of the F-FA fault code, the boiler locks out for a few reasons. As the PCB can’t effectively communicate with the fan, it can’t be sure that it’s working correctly. If the fan isn’t doing its job correctly, harmful gases might not be being vented from the flue. And, that’s going to mean that potentially, the boiler is dangerous.
Another important point worth considering, are repair bills. There’s a chance that the fan can be fixed. However, if it’s not turning off, that means it’s working overtime. That’s going to mean that it wears out prematurely, leading to more repair bills.
Gas appliances like boilers should only be worked on by Gas Safe registered engineers. So, you’ll need to call a boiler repair company to come and assess your boiler. Once they’ve fixed the problem, they’ll be able to reset your boiler, clearing the F-FA fault code in the process.
How will my boiler engineer know if the fan is faulty
The first thing they’ll need to check, is that the wires and connections to and from the fan are in good condition. If they’re not, there’s going to be sporadic communication between the fan and PCB. And, that might mean that when the PCB tells the fan to turn off, it’s not receiving that signal.
Your Gas Safe boiler repair company will be able to check the fan’s electrical integrity, by using a multi-meter. If they manage to isolate any damaged sections of wiring, these will need to be repaired. Your engineer should be focusing on the 100A wire. If this is faulty, the communication between the fan and the PCB is going to be non-existent.
And, if any connections are loose, securing these may resolve the issue. A simple reset will then clear the F-FA fault code from your Viessmann boiler.
But, not all fan faults can be fixed. If your fan is not getting any power and is beyond repair, you’ll need a replacement.
How much is it going to cost to replace the fan on my boiler
The cost of replacement parts on boilers is going to be directly related to the model. A fan could cost as little as £200 and as much as £300.
And, whilst the job should only take a day to complete, it’s likely to be 2-3 days before the repair is finished. Most boiler engineers won’t have spare fans on their vans. So, they’re going to have to order them in from their local supplier.
My boiler repair company thinks that the PCB is the problem, does this sound correct
The PCB is the central control hub for your boiler. If it doesn’t work, your boiler is going to act strangely. This might be things such as the boiler cycling on and off, turning on at random, or not being able to heat up radiators to their optimum heat.
Likewise, this can also cause problems with the fan. If the communication error isn’t the fan’s fault, there’s a good chance that it’s the PCB instead.
To determine if the PCB is at fault, your boiler engineer will test it in a similar manner to which they did with the fan. They’ll use a multi-meter and isolate wires, connections and the PCB itself. They’re looking to see that all aspects of the fan, wiring and connections are getting power.
As with the fan, minor repairs can usually be made to wiring and connections. However, if the PCB isn’t getting power and is at fault, it’s going to need to be replaced.
I need to replace the PCB, how much will this cost
Just like the fan, the price of a replacement PCB will vary by boiler model. However, PCB replacements consistently tend to be in the £400-500 range. Typically, we’d expect the job to take one working day, assuming your engineer has instant access to parts from their local supplier.
And, with repairs of this magnitude, we’d suggest asking your boiler repair company to assess the overall state of your boiler. For small boilers, new installation costs can be as little as £1,800. They’ll come with a long warranty, not to mention that because they’re more efficient, you’ll be making a cash saving every single month on your energy bills.
To determine what the most cost effective route forward is, we’d suggest having your engineer check expensive parts such as the fan, PCB, heat exchanger, gas valve and diverter valve.
My boiler engineer thinks components have been damaged by moisture, how is this possible
It’s important not just to fix the problematic part that’s causing the F-FA fault code to be displayed, but the root cause of the problem too.
Water damage is a major killer of boilers. And, if that’s what has caused the fan or PCB on your boiler to fail, this needs to be looked at as soon as possible.
On most occasions, water damage stems from two components; the heat exchanger or the pump.
The heat exchanger can crack and leak if it’s exposed to limescale. Limescale builds up in the heat exchanger, causing a hot spot, and that eventually leads to a weak spot cracking. It’s this crack that’s going to cause a leak.
In this case, the heat exchanger needs to be replaced, but the system also needs to be flushed of limescale.
If it’s the pump that’s causing the problems, it’s likely the problem stems from blown pump seals. This could be from the old age, but most likely, from a blockage in the system.
We find that a combination of central heating sludge and air locks, cause a blockage in the pump that puts it under excess strain. This eventually blows the seals, and leaking water drips onto important electrical components.
Assuming the pump is in good condition asides from the seals, it can be reconditioned using a service kit.
Other Viessmann boiler issues
For more boiler issues regarding the Viessmann Boiler then please visit the Ideal Boiler Problems And Cures page.