Viessmann Boiler FE Fault Code
The Viessmann fault code FE relates to the PCB and here we have Q & A or require an engineer for an emergency boiler repair.
The Viessmann Boiler Fault Code FE Error Common Q & A
Just below, we have a list of common questions relating to the FE fault code on the Viessmann Boiler.
- What does the FE fault code mean on my Viessmann boiler?
- What does the PCB do on my boiler?
- How will I know if my PCB is to blame?
- Is the FE fault code one that can be fixed on a DIY basis?
- Will a reset fix the FE fault code?
- How will my boiler engineer know if the PCB is faulty?
- If wiring is frayed, can it be repaired?
- What problems should they expect to find with connections on the PCB?
- My boiler engineer thinks that a new PCB is the best option, how much is this likely to cost?
- With these high repair costs, should I consider a new boiler?
- What could have caused the PCB to fail on my Viessmann boiler?
- How can my boiler engineer check and fix a heating pump leak?
- If the heat exchanger is to blame for a leak, can it be fixed?
What does the FE fault code mean on my Viessmann boiler
If the FE error code is being shown on the display panel of your boiler, the most likely cause is a faulty printed circuit board (PCB).
What does the PCB do on my boiler
The PCB is the most important part on your boiler; it controls all other electrical components.
As an example, when you turn up your heating thermostat, the PCB recognises. It will command the gas valve to open, allowing more fuel into the burner. It will monitor the air pressure switch to ensure there’s a change in pressure, signifying that the fan is working.
And, it will also monitor the NTC thermistors on the flow and return pipes. These sensors monitor resistance, which the PCB can turn into temperature readings. With these readings, the PCB can determine whether the water temperature is correct. If it’s not, it will lockout and display a fault code.
Unfortunately, when there’s a problem with your PCB, however small, it can cause a whole host of errors with your boiler.
How will I know if my PCB is to blame
Besides errors like the FE fault code indicating there’s a fault with the PCB, there are some other tell tale signs.
Typically, we’d expect to see one of the following, prior to the PCB determining that the FE fault code is the most suitable:
- The boiler cycles on and off at random
- LED display has been intermittent, or the lights have failed completely
- Controls on the display panel don’t respond
- Burning smells coming from the boiler
- Hot water or radiators don’t get up to temperature
Essentially, if your boiler is acting unusually, there’s a good chance that an aspect of the PCB unit is to blame.
Is the FE fault code one that can be fixed on a DIY basis
Some basic faults on boilers can be fixed without taking the appliance apart. An example would be topping up the boiler’s pressure using the external filling loop.
However, the FE fault code isn’t an error that can be fixed on a DIY basis. The boiler will need to be taken apart to pinpoint the exact problem.
You shouldn’t be taking apart a boiler if you don’t have the suitable experience and qualifications. Instead, you’ll need to call a Gas Safe emergency boiler repair company. They’ll have engineers on hand that will find and fix the problem.
Will a reset fix the FE fault code
You shouldn’t reset your boiler. The reset function should only be used after the problem has been fixed by a Gas Safe engineer.
Resetting your appliance could trick the boiler into working for a few minutes. This could either be dangerous or could lead to internal components being exposed to even more damage, and that means more repair bills.
How will my boiler engineer know if the PCB is faulty
Although the FE fault code states that the PCB is the problem, the appliance still needs to be analysed. Some PCB failures can be fixed, whereas others will lead to the PCB needing to be replaced. And, the difference between the two could be hundreds of pounds. So, it’s worth taking the time to see if the PCB can be repaired.
Your boiler engineer will first, need to use their multi-meter. They’ll test wiring, connections and the main PCB. What they’ll be looking for, is lack of power.
If wiring is frayed, can it be repaired
If your boiler repair company can pinpoint the problem to small sections of wiring, it’s likely they can be repaired. Before repairing them, they’ll want to isolate the problem, ensuring that once repaired, nothing else interferes with the PCB’s ability to operate, causing the FE fault code to be displayed again.
What problems should they expect to find with connections on the PCB
On the PCB, there are several soldered connections. There’s a chance that these are either burnt out or have come loose. If they need securing via soldering, this is a quick and cheap fix. And, depending on the damage, even burnt out connections can sometimes be fixed.
My boiler engineer thinks that a new PCB is the best option, how much is this likely to cost
If damage to the PCB is extreme, it’s likely your boiler engineer is going to suggest a replacement. There’s little point spending time and money fixing a PCB, if it’s likely to fail soon due to it being in extremely poor condition.
A PCB replacement could be anywhere between £400-500, which is going to include parts and labour. The job will take around one working day, if your boiler repair company has access to all the parts they need from their local supplier.
With these high repair costs, should I consider a new boiler
This is a good question, and it depends on the current state of your boiler. If your boiler is relatively new, its likely many important components are in good condition, and will last for years to come. So, a £400-500 investment to repair a boiler that will last for years, is going to be a good one.
However, PCBs tend to fail due to old age. And, that means other parts in your boiler are likely to fail soon too.
The best thing to do, is to get your boiler engineer to check all the most expensive boiler parts. If these are likely to fail soon, a replacement is likely to be a better option. Expensive parts worth checking besides the PCB include the:
- Gas valve
- Fan
- Air pressure switch
- Pump
- Heat exchanger
Alongside the condition of parts, it’s worth considering how old and inefficient your boiler is. New boilers are around 89% efficient, with some older boilers being as low as 60%. That represents a huge cost saving on energy bills.
What could have caused the PCB to fail on my Viessmann boiler
Besides old age, there’s a big killer of boilers, and PCBs in particular; water damage.
If your boiler has a leak, it’s going to cause havoc when it comes to all the internal electrical components. And, that’s because older boiler’s electronic components aren’t as well sealed as they are on newer boilers.
The question is, where do these leaks come from, and can they be fixed to stop this happening again?
Typically, we find that boiler leaks either come from the heating pump, or the heat exchanger.
How can my boiler engineer check and fix a heating pump leak
On visual inspection, a heating pump leak will become obvious. In general, the leak stems from faulty seals. This might be seals that have worn due to old age or, have been put under excess pressure due to the pump being on too high a speed setting, and heating sludge blockages.
Assuming the pump is in good condition, your engineer will want to use a pump service kit to replace the seals, and check the pump’s speed setting.
If heating sludge has caused the issue, this can be cleared manually. And, to clear sludge from the heating system, they’ll want to flush it out using a specifically designed cleaner.
Whereby the pump needs replacing, expect costs to be in the region of £250.
If the heat exchanger is to blame for a leak, can it be fixed
The heat exchanger is one of those components that it rarely makes sense to fix. A leak will have come from a crack, and in this scenario, it makes sense to replace the whole heat exchanger.
Unfortunately, the cost of a heat exchanger can be upwards of £400. Alongside PCB replacement costs, you could be talking about an £800+ repair bill. In this scenario, it’s most likely a replacement boiler is going to be the best option.
However, if you do decide to replace the heat exchanger, the cause of the crack and leak needs to be fixed. It’s most likely been caused by limescale build-up. Like heating sludge, limescale build-up can be removed by using specifically designed limescale removal chemicals.
Other Viessmann boiler issues
For more boiler issues regarding the Viessmann Boiler then please visit the Ideal Boiler Problems And Cures page.