KegLand - RAPT Temperature Controller - Hands on Review

It's widely agreed among brewers that temperature control during fermentation is a critical factor in making the best beer you possibly can. Lack of temperature control can allow the exothermic process of fermentation to cause the temperature of the fermenting wort to spiral upwards, which is known to cause some undesirable off flavours to be imparted into the beer.

This is where temperature controllers come in. What once were relatively simple devices with a temperature probe and relays that open/close electrical circuits to power devices for heating or cooling, have now evolved into smart, internet connected devices that can do this plus so much more.

RAPT Temperature Controller Box

The concept in itself is pretty simple. Use the temperature probe to check the temperature of your wort. If it reaches a set threshold/difference or hysteresis from your target temperature, then the controller will switch on either a heating or cooling plug/circuit to power on a device like a fridge or heat mat to adjust the temperature accordingly. 

The RAPT Temperature Controller does all this, plus much more, so let's dive in and see what it's about.

First off, the packaging is simple and minimalistic, coming in a basic cardboard box with a QR code directing to the user manual plastered on the front. Open the box and we've got our controller neatly packed inside.

RAPT Temperature Controller Packed into Box

No doubt the first thing that jumps out is the coloured cables and plugs for heating (red) and cooling (blue). Both rated at 240V output, there is certainly no mistaking which one is which. We've also got a thinner black lead with the temperature probe on the end. With a rated temperature range from -20C to 120C it will certainly cater for all temperature ranges required for brewing and fermenting. Lastly we have the thicker black lead for main AC power connection to the controller.

The control box itself is kind of chunky, but is cleverly designed to allow a number of different mounting options - though some configurations require re-routing how the four separate physical cables protruding out of the control box (main AC power, temperature probe, heating and cooling outlets/plugs). No doubt some will appreciate the flexibility here, but for us the standard configuration is fine and allows the controller to be mounted from a single or double screw heads with the cables hanging straight down. If you're after more details on mounting options, they're covered in detail within the RAPT Temperature Controller Instruction Manual.

For controlling the device we have 4 physical buttons, giving functions for up, down, enter/select, and back/return. The button styles and appearance of the controller is similar to that of the control panel on the BrewZilla Gen 4 units, giving a consistent look and feel to the RAPT products and ecosystem that KegLand are developing.

Powering on the device and we've got a decent sized colour LCD screen. The resolution isn't particularly high by today's standards, but it's adequate for what it's purpose is here, and the fact that it's colour is a welcome inclusion. Interestingly, the screen is always on/lit up and as far as we can tell there aren't any options or modes for it to dim, go into a sleep/standby mode, or utilise some kind of screensaver. This would no doubt effect the longevity of the screen itself, or perhaps risk the issue of "burn in" from the same image being presented on screen for extended periods of weeks, months or even years. Replacement screens are available as a spare/serviceable part for AU$49.95 though.

Upon powering on the controller for the first time, we're immediately presented with a screen advising us to connect to the controllers own Wi-Fi network (SSID) to configure it to connect to our home Wi-Fi network. 

RAPT Temperature Controller - Initial Connectivity Prompt

It's worth mentioning though that this device can be used offline without any Wi-Fi internet connectivity as all the configuration options needed to get it operating as a basic temperature controller are available through the onscreen menus using the built in button controls.

We're self-confessed geeks at heart though, so of course we're going to get this thing online. After connecting to the controllers Wi-Fi network using our phone, we're presented with the same esp32-wifi-manager/portal used by the RAPT Pill that allows us to find and connect the controller to our home Wi-Fi network in a couple of quick and easy steps. The controller is only compatible with the older 2.4GHz wireless band though - which offers better range and penetration through walls and other objects (like fermentation fridges and stainless fermenters) compared to the newer 5GHz band, but means that users will need to make sure their wireless modem/router has 2.4GHz Wi-Fi enabled.

Once connected to Wi-Fi, the controller prompts us to initiate the registration process from the controller menu itself, then complete the registration online through the RAPT Portal by entering the MAC address and Validation Codes as displayed on the screen. If you haven't used or accessed the RAPT Portal before, registration is simple and free, and your sign in/authentication can be integrated with your Google or Facebook accounts for ease of access and so you have one less password to remember.

RAPT Temperature Controller - Registration Prompt

All in all this registration process was quick and painless, and we had the controller registered in the RAPT Portal in a matter of minutes. The on-screen prompts are clear meaning users can follow on without needing to resort to the user manual.

We then initiated an Over The Air (OTA) update to ensure the controller was running the latest available firmware - as is good practice with any internet connected device. The option to initiate the update was easily accessed via the menu, downloaded and installed quickly, rebooted and we were back up and running again.

RAPT Temperature Controller - OTA Update Screen

We did encounter an issue shortly after this where the registration on the Temp Controller itself seemed to have become broken and it was prompting us on the screen to register the device again. After a bit of mucking around we figured out that we had to select the "Clear Registration" menu option to reset it that then allowed us to Register the device again. This was perhaps an issue initiated by the firmware update, and ultimately wasn't a big deal as everything started working again correctly after re-registering the device to the RAPT Portal.

The screen itself is host to a decent amount of information. In it's default format, the screen displays the current temperature probe reading in a large text in the middle of the screen. The date and time are in the top left corner, Wi-Fi signal strength and heating, cooling alarm icons are in the top right corner, and the target temperature is located in the bottom left corner.

RAPT Temperature Controller - Main/Home Screen (Default)

This display can also be adjusted to show a temperature history graph in place of the current temperature reading in the middle of the screen, with options to show temperature history for periods ranging from the past 7 hours to 14 days as shown below.

RAPT Temperature Controller - Graph Display

Diving into the RAPT iPhone App now and after selecting our Temperature Controller, we can access the Settings tab to configure our temperature settings, delay times and telemetry frequency options. As previously mentioned, these settings can also be adjusted directly from the Temp Controller as well using the onboard buttons.

RAPT Temperature Controller Settings in RAPT Portal/App

After making changes through the app, they are pushed back to the controller immediately. We did encounter some frustrations with the RAPT iPhone App as well where the grey, blue and red buttons (pictured above) were cutoff from the bottom of the screen, and the scrolling up/down didn't work correctly to make them more available/accessible. Hopefully this will be addressed in due course, but the full web browser based portal doesn't appear to suffer from this issue.

Another really cool feature that is offered by the RAPT Temperature Controller is for it to act as a bluetooth repeater. The most common use case for this at the moment is to address an issue that we encountered ourselves, which was the inability for our RAPT Pill to connect to our Wi-Fi network for submitting telemetry to the cloud when using it in a stainless steel fermenter in our fermenting fridge.

RAPT Temperature Controller - Bluetooth Devices Screen

Using the Pill in this manner essentially has it in a type of faraday cage, with the stainless walls of the fermenter, and thick insulated walls of the fridge blocking the wireless signal from penetrating. The RAPT Temperature Controller gets around this by allowing the RAPT Pill to be "bonded" to it via Bluetooth - which does have a strong enough signal to penetrate through a stainless fermenter and fridge wall (assuming they're located reasonably close together) - and will receive the telemetry from the Pill, then submit it to the RAPT Portal using it's own Wi-Fi connection. A clever solution to a problem that saves people from messing around with Wi-Fi range extenders, or other rudimentary solutions.

The steps involved pairing the Temperature Controller and Pill together are a little more involved. and require the latest available firmware update to be installed on the RAPT Pill, as well as adjusting settings within the Pill, RAPT Portal and Temperature Controller to have them all work together harmoniously. We didn't have any difficulties though and got it all up and running fairly quickly. Check out our  guide on How to connect RAPT Pill to RAPT Temperature Controller for detailed instructions on how to accomplish this.

So, what are the benefits of having an internet connected temperature controller like this, besides being able to adjust and configure settings remotely? Well, as you'd expect, through the RAPT Portal (app or website), the temperature controller will display a neat timeline and graph overlayed with historical data showing the target temperature, actual temperature from the temp probe.

If you integrate it with the Rapt Pill you'll get additional data overlayed on the graph for gravity readings, alcohol content and Pill temperature, in addition to the readings provided by the temperature controller for set temperature and actual temperature according to the temperature probe.

As you can see from the sample above, the red line indicates the set/target temperature, blue line indicates the temperature reading on the probe, and the green line represents the temperature from the RAPT Pill. The yellow line represents the gravity readings and the faint red dots (that intersect the yellow line) represent the alcohol content (ABV%).

That's not all though - there is also a neat feature called "profiles" that allow pre-defined steps to be run on the temperature controller to maintain and adjust the temperature accordingly for set periods of time. Here's a test one we setup as an example;

Step 1 - target temperature 18.5C for 7 days for primary fermentation
Step 2 - target temperature 21C for 3 days for diacetyl reset
Step 3 - target temperature 12C for 2days for soft crashing and dry hopping
Step 4 - target temperature 1C for 3 days for cold crashing/packaging.

This is all done within the RAPT Portal and gives a neat list and graphical view of the profile you have setup - as pictured below (click the image to make it larger and easier to read).

RAPT Portal - Sample Temp Control Profile

At the time of writing this article, steps can only be configured based on time/duration in days, but I'd expect this will be further developed in the future to allow triggers to be set using gravity readings from the Pill. For example, you could set the profile so that Step 2 outlined above is triggered when your expected final gravity (FG) is reached and detected by the Pill.

The possibilities are almost limitless, and essentially allow a "set and forget" methodology for managing your fermentations which would undoubtedly benefit some brewers who aren't able to constantly check and manage their temperature controller manually for whatever reason.

We'd consider KegLand's RAPT Temperature Controller an excellent piece of gear. The bells and whistles of internet connectivity, profiles and bluetooth repeater functionality may not be for everyone, but for those who are entering into the RAPT ecosystem with products like the RAPT Pill, the integrations that are being developed to have these devices work together make it well worth considering. 

At the current price point of AU$99.95, it's certainly more expensive other temperature controllers, including Wi-Fi connected ones like the Inkbird ITC-308, however it differentiates itself fairly significantly from the rest of the pack with features the competition just don't currently have. If you plan on using a device like this to it's full potential, then the price tag is easily justifiable.

The RAPT Temperature Controller is available from the KegLand website.

Update 21/11/2022

Having used our RAPT Temperature Controller for a number of brews, we decided to compare it's accuracy against our Inkbird Temperature Controller, as well as a standalone meat thermometer and  discovered that the RAPT device was reading approx 3°C lower than the actual temperature. We strongly recommend anyone who purchases one of these to perform a temperature probe calibration as part of the setup - we've documented the process which you can view by following the link below;

RAPT Temperature Controller - Temperature Calibration Process

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