or **Down** 
buttons to navigate. Use the **Select** 
button to select or enter a function once highlighted. Use the **Return** 
button to escape from a Menu option or return to the prvious screen. Selecting Back will not save any changes.
### Register Device
This option will only be available when the RAPT Gen 4 BrewZilla is *not* registered to the RAPT Portal. For a step by step guide to registering your RAPT Gen 4 BrewZilla please refer to [Getting Started](https://docs.rapt.io/equipment/rapt-brewzilla/get-started)
### Profiles
To access currently running Profiles, or Profiles that have been uploaded to the device, navigate to and select **Profiles** in the menu. From this menu, available Profiles can be started, stopped and paused.
Active profiles can also be skipped to another step or reverted to a previous step. Please refer to [Profiles ](https://app.gitbook.com/o/wlVNEjFt3UiW0iKxpA2G/s/UqN4sW0x2s4yh6iiT8NN/~/changes/109/equipment/rapt-fermentation-chamber/profiles)for a full guide.
### Delayed Start
Delayed Start is a smart timer that allows (for example) the strike water to be heated to a set temperature at a set time. This is useful if you wish to brew early in the morning - you can fill the BrewZilla and select the time you want the mash water to be ready.
To input a Delayed Start temperature and time, first enter the desired temperature using the **Up** or **Down** buttons. When the desired temperature is displayed, press **Select** to move to the next field.
The next field is the time in hours and minutes the temperature should be reached. Enter the desired time using the **Up** or **Down** buttons.
**NOTE**: If the BrewZIlla is connected to WiFi and Registered to your RAPT Account, a dynamic display will show the time and date at which the input temperature will be reached.
Once the desired time has been reached, press **Select** to move to the next field. The next field allows you to *include* or *not include* heating time. If **Yes** is selected, **heating time will be included**. This means the BrewZilla will start heating *before* the selected time such that the target temperature is reached at the selected time. If **No** is selected, the BrewZilla will start heating at the selected time.
Once all setting s are correct, press **Select** to save the Delayed Start. The BrewZilla will now automatically begin heating at the selected time.
**NOTE: The BrewZilla will be automatically set to heat at 100% power when Delayed Start is active. Heating time calculations are based on 100% power.** The power setting can be manually changed once the Delayed Start has been set. However, this will not be allowed for in timing calculations and is therefore not recommended to be changed.
**Delayed Start** can be cancelled at any time. Open the menu and select **Cancel Delayed Start** to cancel.
[**Profiles** can also be started using the **Delayed Start** option.](https://docs.rapt.io/equipment/profiles#starting-a-profile) This is performed through the **Profiles** screen
### Settings
The following options are available in the **Settings** Menu.
To change any of the advanced settings enter the Menu by pressing **Select** . Once in the menu navigate to Settings and press **Select**
**Up** or **Down** buttons to adjust the set value for the setting. To save your setting hit **Select** . To return to the menu without saving choose **Cycle/Back** 
Some options are on/off toggles that can be activated or deactivated from the Settings Menu directly.
| SETTING | PARAMETER |
|---|---|
| Temperature Sensor | Select built-in probe or select any Bonded Bluetooth RAPT Pill & Hydrometer |
| Show Graph | Toggles display between the graph or a numerical display |
| Unit System | Toggles between metric or imperial data |
| Graph zoom level | Select the date range displayed on the graph (default 7 days) |
| Heating Hysteresis | Sets the heating hysteresis (range 0.0°C-10°C, default 2°C) |
| Heater Enabled | Toggles heating on or off (when unchecked, the heater will not operate irrespective of other settings) |
| Bluetooth Enabled | Toggles Bluetooth functionality on or off |
| Allowed Sensor Diff. | This sets the allowed temperature differential between the built in probe and the current setpoint when using a Bluetooth device for temperature control (range 1°C-50°C, default 2°C). See Bluetooth Operation |
| Sensor timeout | Sets the timeout if a Bluetooth device drops out (reverts to internal probe) (Range 5-1800 seconds, default 130 seconds) |
| Sounds Enabled | Toggles device sounds on or off |
| Calibration Point 1 | First Calibration Point (see Calibration) |
| Calibration Point 2 | Second Calibration Point (see Calibration) |
| Forget Calibration | Deletes saved calibration settings and restores defaults |
| NTC Beta | Enter the NTC Beta of an external temperature probe. The default is 3950 |
| NTC Ref. Temperature | Enter the NTC Ref. Temperature of an external temperature probe. The default is 298.2 |
| NTC Ref. Resistance | Enter the NTC Ref. Resistance of an external temperature probe. The default is 100000 |
| Relay Cycle Time | Sets the allowed cycle time for PID heating (Range 5-3600 seconds, default 30 seconds) |
| Distillation Mode | Toggles Distillation Mode on or off |
| PID Heating | Toggles PID heating on or off (recommended for advanced users only) |
| Heat P Coefficient | Enter desired proportional PID coefficient (Default 0.250) |
| Heat I Coefficient | Enter desired integral PID coefficient (Default 0.0100) |
| Heat D Coefficient | Enter desired derivative PID coefficient (Default 0.0750) |
| Forget WiFi Config | Forgets existing WiFi config - useful if you change WiFI networks |
| Disable WiFi | Disables WiFi (if you wish to not use the RAPT Portal and have only manual control) |
| Clear Registration | Clears RAPT Portal registration (see Troubleshooting) |
| Low Temp. Alarm | This is the temperature below which an alarm will sound (default -10°C) |
| High Temp. Alarm | This is the temperature above which an alarm will sound (default 120°C) |
| Check For OTA Update | Manually check and download any available firmware updates |
or **Down** buttons to scroll to select the device. Choose **Select** button to **Bond** the device, or the **Cycle/Back** button to cancel.
Once **Bonded**, the device will be visible in the **Bonded** section of the **Bluetooth Menu**. To **Unbond**, select the device with the navigation arrows and choose **Select** buttont to **Unbond** the device, or the **Cycle/Back** button to cancel.
Once the device is **Bonded**, it can be selected in the **Settings** menu option as one of the available Temperature Sensors. Once selected in this menu, temperature control will be ceded to the selected Bluetooth enabled RAPT device, rather than the internal temperature probe. In addition, on the TFT display the current (most recent) Gravity and Temperature reading will be displayed. The internal (built in probe) temperature is also displayed.
**NOTE**: this is not displayed in Graph Enabled Mode.
**NOTE: It is completely normal for there to be a temperature variance between the built in probe and the Bluetooth enabled RAPT device.** This is because the Bluetooth device is measuring the temperature of the mash (typically), and the built in probe is measuring the temperature at the base of the boiler. This difference will be greater when the RAPT Gen 4 BrewZilla is actively heating.
The **Allowed Sensor Diff**. Iin the [Settings ](#settings)menu) sets the *allowed* temperature differential between the *desired setpoint* and the *current temperature* of the RAPT Gen 4 BrewZilla's built in probe. Heating is disabled temporarily if this differential is exceeded. The default differential setting is 2°C. This value is suitable for mashing. For step mashing or mash out (for example) you may wish to increase this differential as this allows the temperature of the mash to be incresed at a faster rate.
This differential can be altered in the **Settings** menu. If the temperature differential is exceeded, the RAPT Gen 4 BrewZillawill suspend heating until the differential is reduced. The legend **DIFF OVERRIDE** will also be displayed when the display is in Graph Disabled Mode.
The RAPT Gen 4 BrewZilla will suspend active heating and resume as needed – no intervention is required. Once the differential is reduced then heating will continue as normal.
For more information about Bluetooth operation, plase refer to the Bluetooh section.
### Diagnostics
The Diagnostics menu contains information about the RAPT Gen 4 BrewZilla. This includes such information as current firmware version, Wi-Fi network and signal strength, MAC address and IP address of the device.
### About
The About menu contains information specific to the firmware and software of the RAPT Gen 4 BrewZilla and associated devices, including but not limited to copyright information, acknowledgment of open source properties used, legal information etc.