Troubleshoot error code “F56” in Vaillant boiler

  • Error: “F56”
  • Description: Safety disconnection due to exceeding the CO limit value.
  • Cause: Defective component in combustion regulation, contact error in the gas valve.
  • Solution: Review and possible replacement of the gas valve.

When your Vaillant boiler displays the error code “F56”, it’s time to pay attention and take action to solve the problem. This error can indicate that something is not working correctly in your heating system. Below, we explain what this error means, why it occurs, and how you can solve it.

What Does Error F56 Mean?

The “F56” error in Vaillant boilers indicates that the system has detected an exceeding of the carbon monoxide (CO) limit value, which has activated a safety disconnection. This is a protection mechanism to prevent dangerous situations for the occupants of the home.

Why Does It Occur?

This error can be caused by several factors, including:

  • Defective combustion regulation: If the combustion system is not working correctly, it can produce an excessive amount of CO.
  • Contact error in the gas valve: A poor contact in the gas valve connection can affect the flow and mix of gas, resulting in inefficient combustion and the production of CO.

Step-by-Step Solution

  1. Boiler Reset: As a first step, try resetting your boiler. This can solve the problem if it was a one-time error.
  2. Review of the Gas Valve:
    • Check connections: Make sure all connections to the gas valve are tight and there are no signs of damage.
    • Visual inspection: Look for signs of corrosion or damage to the gas valve.
  3. Contact a Professional: If the error persists after resetting the boiler, it is crucial to contact a specialized technician. This error involves risks related to combustion and carbon monoxide, so it requires professional review.
  4. Preventive Measures:
    • Regular Maintenance: Schedule periodic reviews of your boiler to ensure its proper functioning and prevent future errors.
    • CO Detectors: Consider installing carbon monoxide detectors in your home as an additional safety measure.

Other error codes in Vaillant boiler

Troubleshoot error code "F57" in Vaillant boiler

Troubleshoot error code “F57” in Vaillant boiler

Error: "F57" Description: Failure during comfortable safety operation. Cause: Intense corrosion on the ignition electrode. Solution: Inspection and possible replacement of the ignition electrode. When your Vaillant boiler displays the ...
Troubleshoot error code "F54" in Vaillant boiler

Troubleshoot error code “F54” in Vaillant boiler

Error: "F54" Description: Gas pressure failure (in combination with F.28/F.29). Cause: Non-existent or too low gas inlet pressure; gas valve closed. Solution: Check gas pressure and ensure that gas valves ...
Troubleshoot error code "F53" in Vaillant boiler

Troubleshoot error code “F53” in Vaillant boiler

Error: "F53" Description: Failure in the circulating flow sensor. Cause: This error can be due to several reasons, such as insufficient gas flow pressure, wet or clogged filter cap of ...