If your controller won't connect — or you're seeing messages like "Verification Failed" — work through this checklist step by step.
1. Check your WiFi network
The controller only supports 2.4 GHz WiFi.
- Make sure your router has 2.4 GHz enabled.
- If your router combines the 2.4 GHz and 5 GHz networks under one name (SSID), you may need to temporarily separate them or enable a dedicated 2.4 GHz network.
- Every router is different, so check your router or modem manual if you're unsure how to do this.
Note: the controller cannot connect to a 5 GHz-only network.
2. Check IoT compatibility (G40 & G70)
For the G40 and G70, make sure your router allows IoT (Internet of Things) devices. Some routers have settings that block or isolate smart devices from connecting, even when the WiFi band itself is fine.
3. Make sure you're within WiFi range
Poor signal strength can prevent the controller from connecting. Try moving the brewing system closer to your router before attempting to pair again.
4. Clear the saved WiFi credentials
If the controller has previously connected to another network, clearing the stored credentials can help.
On the controller: Menu > WiFi Config > Clear credentials
Then delete and reinstall the app, and try connecting again.
5. Try connecting to a mobile hotspot
This is one of the quickest ways to work out whether the issue is with your home network or the controller itself.
- Turn on the hotspot on your mobile phone (make sure your phone is using mobile data, not WiFi).
- Connect your Grainfather controller to the hotspot.
- If it connects successfully, the issue is likely with your home router or network settings, rather than the controller.
6. Check your WiFi password
Some routers or devices can have difficulty with certain special characters. If your WiFi password contains characters such as @ _ , $ % & ! and similar, try temporarily changing it to only letters and numbers, then attempt to connect again.
Still having trouble?
If you've worked through all of the steps above and your controller still won't connect, get in touch with the Grainfather Support Team with the following details ready:
- Your Grainfather model (GF30, G40, or G70)
- Serial number
- The exact error message you're seeing (if any)
- Whether the controller connected successfully to a mobile hotspot
- Whether you're using a 2.4 GHz WiFi network
- What firmware version your controller is on
- What app version you're using
- The email address used for your app account
Having this information ready helps us diagnose the issue as quickly as possible.