Code 25 — Incorrect PWM configuration

What does Code 25 mean?

Error Code 25 indicates that the Pulse Width Modulation (PWM) signal setup, used to control the pump's speed and flow rate, is incorrectly configured. This often occurs during initial installation or when replacing an existing pump.

• Incorrect settings for PWM signal frequency, duty cycle, or voltage levels
• Damaged or disconnected PWM signal input cable
• Configuration mismatch during replacement of a UPM3 or UPM4 pump

Click steps to track your progress.

1. 1

   Open the Grundfos GO app and navigate to the PWM configuration settings.

2. 2

   Verify that the PWM signal specifications (frequency, duty cycle, voltage levels) are correctly set according to the pump's requirements.

3. 3

   Inspect the physical PWM signal cable for any signs of damage or loose connections.

4. 4

   If replacing a UPM3 or UPM4 pump, use the GO Replace tool in Grundfos GO to ensure correct replication of the PWM configuration.