What does the Vaillant S.37 fault code mean?

Your boiler has temporarily stopped because it cannot get the internal fan spinning at the correct speed to safely clear exhaust gases.

How much does it cost to fix Vaillant error code S.37?

Typical repair cost for the Vaillant S.37 fault is £180-350 including labour.

Waiting time: Deviation in fan speed (Waiting period: Fan failure in operation)

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Each noise points to a different fault.

Safety-critical — turn off, read this.

7 signs repair isn't worth it anymore.