What is the GCAST?
The GCAST is your brew day's little translator. On its own, it doesn't heat, stir, or measure a thing — it's a small Bluetooth-to-Wi-Fi bridge that sits near your G30 Controller (or Tilt Hydrometer) and relays everything back to the Grainfather Cloud, so you can keep an eye on your brew from the app wherever you are.
Without it, your G30 only talks Bluetooth — great in the garage, useless if you've nipped out to the shops mid-mash. The GCAST is what turns "brew day" into "brew day I can watch from the couch."
How it works
- Your G30 Controller (or a Tilt Hydrometer) talks Bluetooth — short range, no internet required.
- The GCAST picks that signal up and re-broadcasts it over your home WiFi.
- It pushes that data up to the Grainfather Cloud, which is what powers remote monitoring, notifications, and session logging in the app.
Features
- More flexibility during brew days with a more reliable connection when brewing with the G30 and the Grainfather App
- Break free from Bluetooth® limitations using your home Wi-Fi network
- Sleek, multi-textured design that can be attached to any magnetic surface
- Quick and easy to set up.
- View live Tilt data from anywhere and log it to your brew session with no additional hardware required
- Backed by a 3-year warranty
What it connects to
- Up to 8 Tilt Hydrometers at once (every colour) — ideal if you're running several fermenters in parallel.
- One G30 Controller at a time over Bluetooth.
Reading the LED
The LED is basically the GCAST's whole personality. Here's the cheat sheet:
| Colour | Pattern | Meaning |
|---|---|---|
| Blue | Pulsing | Setup / connection mode |
| Yellow | Flashing | WiFi details saved, not yet connected |
| Green | Slow flash | Connecting to your WiFi network |
| Green | Fast flash | Connecting to the Grainfather Cloud |
| Green | Solid | Connected and online — you're good to go |
| Purple | Flashing | Firmware updating — don't unplug it |
| Red | Flashing | Critical error — contact Customer Service |
Firmware updates
Updates are pushed Over-The-Air (OTA) automatically — no manual downloads, no app store faff. You'll see the purple flashing light while it installs. We've done this before (a v3.8 rollout in 2024 tightened up performance and security), and it reaches every activated unit without you lifting a finger.
Does it need calibrating?
No. The GCAST isn't a measuring device — it's purely a signal bridge — so there's nothing on it to calibrate. Calibration only applies to the gear it's relaying data from:
- Tilt Hydrometer — calibrated through the separate Tilt app
- G30 boiler volume/temperature probes — can be recalibrated if readings drift, but that's a G30 matter, not a GCAST one
Setup requirements
- WiFi: 2.4GHz only (not 5GHz) — WPA, WPA2, WPA2-Enterprise, and WPS all supported
- Minimum OS for setup: iOS 11 / Android 8
- Minimum OS for ongoing use: iOS 10 / Android 6
Troubleshooting connection issues
Won't connect to WiFi (yellow flashing):
- Hold the side button until the LED flashes blue — this resets the GCAST.
- Re-run the setup steps in the GCAST instructions.
- Still stuck? Check that:
- The GCAST is close to your router with a strong signal
- Your WiFi credentials were entered correctly
- You're on the 2.4GHz band, not 5GHz
- No firewall is blocking the device from reaching the cloud
Won't connect via Bluetooth:
- Make sure your G30 Controller is in the same room, within standard Bluetooth range
- If pairing a Tilt Hydrometer, check that its batteries are charged first