Posted on

EMS-ESP and BBQKees in c’t magazine 02/2026

c’t Magazin 02/2026

The German computer magazine c’t from the big German publisher Heise.de published an article about the open source project EMS-ESP, which is the core of our products. They also covered our EMS Interface board and EMS Gateways.

Front page c't 02/2026 -Copyright Heise Medien GmbH-
Front page c’t 02/2026 -Copyright Heise Medien GmbH-

Article introduction

Article intro c't 02/2026 -Copyright Heise Medien GmbH-
Article intro c’t 02/2026 -Copyright Heise Medien GmbH-

Translation to English: Thermal monitor
Without the cloud: monitoring and controlling heating systems from Bosch, Buderus and Junkers

According to Bosch, you need a connection to the manufacturer’s cloud to evaluate and control heating systems. The open-source project EMS-ESP takes a shortcut and connects the heating system to the local network and open control centres such as Home Assistant and OpenHAB via the EMS protocol. This allows you to bridge the gap and automate your heating system.

Where to read/get it

The article can be read on their heise+ page and of course in the c’t magazine itself which is available from 9 January 2026 in shops and online.

Posted on

Product updates Q3 2025

Product ID fixed

Most products are now getting an internal code ID ‘burned’ into the memory of the ESP32 chip during production to identify the product and the batch number of its’ circuit board.
The latest EMS-ESP development firmware 3.7.3 version 15 or higher will detect this ID and fix the board profile accordingly.
Firmware 3.7.3 is not a stable release yet, but as the latest stable 3.7.2 does not have the internal code to look for this ID, all production boards which contain a product ID are loaded with the 3.7.3 dev15 or higher firmware.

In the past, a faulty firmware update could for instance reset the board profile to the default S32, which would render the Ethernet port inoperable. You would then have to log in via WiFi, set the board profile back to E32 V2 and reboot to get the Ethernet port working.
With the product ID fixed inside the ESP32, the firmware will then automatically recover and use the correct board profile.
If you are a developer who likes to play with custom board profiles on a BBQKees Gateway product, you need to take into account that the default EMS-ESP firmware will keep setting the board profile according to the product ID found.

The product ID is burned into the ESP32 chip, so this is persistent over firmware updates and will even survive a full erase of the flash memory.

How can I check if a product ID has been set?

If you visit the Hardware tab on the Status page of the web interface, the ‘Hardware device’ will show the BBQKees logo and will tell you which board revision and batch number it is.
If it does not show the BBQKees logo and give just the ESP32 chip revision, it will not have the product ID fixed.

Alternatively, you can use the terminal to check. Open a terminal on the Gateway via Telnet or serial en type in ‘show’.

If there is no fixed product ID, the model description will be empty. If a product ID was found, it will show the specification. Below on the left a board with product ID and on the right a board without product ID.

What happens when I load new firmware on a BBQKees product without a product ID?

Nothing will happen to the board settings when you update the firmware on an existing BBQKees product without fixed product ID. So it is backwards compatible.
However, if the product ID is set, any firmware from 3.7.3 dev15 and onward will fix the board profile to the one belonging to the product ID. So custom board profiles may be overruled.
If you use a custom board profile on a genuine BBQKees board you are probably a developer yourself so you will know how to change the board profile back to a custom one.

Discontinuation of the EMS Gateway S3

The manufacturer of the grey enclosure of the S3 and S3-LR Gateways has stopped production entirely earlier this year. We purchased all remaining stock we could find but our S3 enclosure inventory is almost depleted now.

Because of this, we were forced to revisit our product portfolio.
The S3 and E32 V2 Gateway models have only slight differences aside from the absence of LAN/Ethernet on the S3. As the more feature-rich Gateway E32 V2 is already our existing main product, we basically have an S3 ‘successor’ at hand.
Designing an completely new S3-like product in a new enclosure from scratch is a huge amount of work. It’s not just selecting an enclosure and fitting the circuit board to this new box, but you need to go through all the regulatory and compliance testing again which is both a pain in the ass and expensive. And after that create new manuals, instructions, design new packaging, incur new GTIN/EAN fees, etc etc.
Therefore we decided to focus solely on the E32 V2 instead of creating an additional successor of the S3.

Over the past 2 years we had plenty of time to refine the existing E32 V2, which will be able to handle all the stuff we can think of in the coming years thanks to its big and future proof 16MB Flash and 8MB PSRAM memory.

Time frame remaining stock

We will discontinue the S3 product line after the current stock has sold. We expect to sell out within a number of weeks or by the end of Q3 2025 at the latest. So if you like to get your hands on a small WiFi-only EMS Gateway you have to decide soon!
There will not be a sale on the remaining S3 or S3 KIT products. Business customers who would to get some S3 before it sells out, just send us an email for a quote.

The previously available S3-LR will not get into new production anymore obviously (we had a number of people on a waiting list).

Warranty and parts availability

The S3 Gateway will still be supported in future EMS-ESP firmware releases and you still get the 2-year BBQKees warranty. We are committed to long term service and are thus keeping an inventory of spare boards and other S3 parts for warranty replacements.

Posted on

New product packaging for KIT products

It took more effort than expected but finally we have a dedicated product packaging for the E32 V2 / S3 EU KIT products.

It’s a strong cardboard box made from recycled materials. The interior of the box is made from the same plain eco-cardboard material. It fits though the mail slot.

In the coming weeks the old plain packaging will be slowly replaced by this new branded product packaging for the EU KIT versions. Unfortunately the UK plug by design is too big to fit through a mail slot and therefore the UK KIT packaging needs to be bigger. These will continue to be sent in generic cardboard packaging.

BBQKees.com new product packaging

The E32 V2 Gateway sits on the left and the power supply and bag with cables and accessories sit on the right.

E32 V2 KIT product packaging
E32 V2 KIT product packaging

And the same interior piece also fits the S3 Gateway so we have only one interior for both products.

Posted on

28 October 2024: Firmware 3.7.0 release now available

After 6 months and 47 beta versions EMS-ESP32 firmware 3.7.0 has finally been released. It packs hundreds of improvements, new features and bug fixes.

Updating to 3.7.0 from 3.7.0dev

If you were already on a development version of 3.7.0, you can update the firmware via the update feature of the web interface.

Updating from 3.6.4 or 3.6.5 to 3.7.0

If you are currently on 3.6.4 or 3.6.5, you cannot update via the web interface directly.

Clicking on the bin file will result in an error. This is because after 3.6.5 the firmware bin file naming scheme has changed, so the 3.6.5 firmware is looking for a bin file on the Github repository that does not exist.

In this case go to the releases page of the firmware repository and download the correct bin file.

You can use the table here for getting the right file.

After you have downloaded this file to your computer, you can upload it via the EMS-ESP web interface.

After the reboot of the Gateway, press F5 to clear the browser cache otherwise there may still be some left overs of the old interface in the cache, causing strange UI combinations of both the old and the new user interface.

Possible issue with updating to 3.7.0 with the E32 V2

In some cases after the new firmware upload, the Ethernet interface of the E32 V2 may be disabled. Don’t worry, it’s not dead. In these cases the board profile of the firmware has accidentally defaulted to the S32 Gateway, which has no Ethernet.

To correct this, log in to the ems-esp WiFi network, go to settings and change the board profile to E32 V2. Then save and reboot and Ethernet will become alive again.

Posted on

New version of the EMS screw terminal cable

Since the end of April 2024 I have a new version of the EMS screw terminal cable.

It’s still a 100cm cable with two stranded copper cores of 2×0,5mm2 and the wire ends terminated with a wire ferrule, but now the cable is black and a bit thinner and more flexible than the previous grey cable.

You can find the cable here or you can include it as an option on the Gateway and Interface board product pages.

Below on the left the ‘old’ version of the cable and on the right the new version.

Some more product images:

You use this cable to connect the orange or green screw connector of the Gateway to the EMS screw terminal inside the boiler or heat pump.

Posted on

Gateway model E32 V2 now available

It took a bit longer than expected but the first batches of the new Gateway model E32 V2 with WiFi and LAN are now available.

It has all the awesome features of the S3 Gateway with the same EMS-ESP32 firmware but aside from WiFi it has an additional RJ45 Ethernet port for wired networking.
Because the ESP32-S3 chip of the S3 Gateway does not support hardware Ethernet we used a big ESP32 module instead but with a beefy 8MB PSRAM and 16 MB Flash. This solves all the little memory issues of the previous E32 some users might be experiencing with the latest 3.6.x firmware when used with larger EMS systems.

Although the E32 V2 hardware has 8MB of PSRAM, currently the EMS-ESP32 firmware only supports 4MB PSRAM on the ESP32. 4MB is more than enough for now, but if needed this can be increased to 8MB in the future.
Furthermore EMS-ESP32 currently only needs 4MB of Flash storage, so with 16MB of Flash storage in the E32 V2 there is lots of room for more features.

Because the circuit board did not fit anymore into the grey enclosure of the E32 V1.0/V1.5 and the S3 a new enclosure was created. It also has mounting holes on the back. Furthermore it is UL 94 V level fire retardant.

The E32 V2 went through several rounds of prototyping and is of course CE certified and manufactured according to the RoHS directive.
The LAN port provides a very stable interface. POE is not included though, non-isolated 48V is not a good match with the 16V EMS bus.

Currently there may be limited availability of this model, from March onward continuous stock is expected.

You can find it in the webshop HERE.

If you don’t need LAN the cheaper WiFi-only S3 and S3-LR are still a great choice as well.

Posted on

Improved wall mount bracket

The wall mount bracket for the S3, S3-LR, S32, E32 and older models is 3D printed.

We are now printing the brackets on a Bambu Lab X1 Carbon printer. The quality has been improved dramatically.
The left image shows the ‘old’ bracket on the left versus the ‘new’ bracket on the right. both are printed with the same filament. You can now hardly see it’s 3D printed.

EMS Gateway new bracket
EMS Gateway bracket comparison
Posted on

New Gateway models S3 and S3-LR available

As time progresses so does the EMS-ESP firmware. We were now at a point were EMS-ESP would benefit from some more RAM memory.

That’s why BBQKees Electronics is introducing the new EMS Gateway S3 models. One with the default on-chip antenna and an identical Gateway model with an external high gain antenna for those area’s with low WiFi reception. These are the replacement for the very popular S32 Gateway.

S3-LR front
S3-LR back

Hardware changes

The S3 models looks and feel identical to the EMS Gateway S32 V2.0 they are replacing but they now come with an ESP32-S3 module with 16MB Flash and a hefty 8MB PSRAM (in addition to the on-chip 512KB RAM), which makes it more suitable for large EMS systems with a heat pump or multiple zones/heating circuits.

The new hardware continues using the existing third-gen BBQKees EMS detecting and sending circuitry design as in the S32 Gateway and the EMS Interface board V3’s, which has proven extremely reliable and robust over the years for all EMS types across all Bosch brands.

Aside from the more powerful chip, this model now also features an external USB-C connector for manual firmware updates (if ever needed). The USB-C connection makes use of the internal USB OTG controller of the ES32-S3 so we don’t need the CH340 chip and driver anymore.

What has remained unchanged are the positions and pinout of the external connectors so the S3 is a direct replacement for S32 setups. Only the LED lightguide was changed a bit.

The power options via the service jack or 12V DC power supply also remained the same.

Firmware

The S3 models will be loaded with firmware EMS-ESP32 v3.6. This is exactly the same firmware with the exact same features as for the S32, just built for the different chip architecture of the S3.
The 3.6 firmware contains a number of new features over 3.5.1, most notably further memory optimizations.

Upgrade discount

If you already own an S32 Gateway it’s probably not really worthwhile to upgrade to the new S3, but if you want too or if you still have an old ESP8266 Gateway like the Premium II you can get a 15% discount on a new S3 Gateway of your choosing. Just use the contact form to contact me with your previous order ID and I’ll give you a discount code.

Posted on

New upgrade module for Premium II and older Gateways available

The ESP8266 module in older Gateways like the Premium II can be upgraded to another module in the same format.

The MH-ET Live ESP32 module was a good choice to upgrade the ESP8266 to an ESP32 chip.

Now available in the webshop a soldered and LilyGo T7-S3 board with an ESP32-S3 chip and 16MB Flash and 8MB PSRAM. It’s programmed with EMS-ESP for your convenience.
This new upgrade module is so powerful you probably never need any other upgrade again.

LilyGO T7-S3 on old ESP8266 Gateway

For the ESP32-S3 a different bin file is available on the EMS-ESP repository for EMS-ESP 3.6 and later.

For upgrade instructions see the wiki.