Premium II base board

The base board of the Premium II Gateway was also sold seperate from the complete Gateway.

Compatible ESP8266/ESP32 board

The base board has two headers which were intended for the Wemos D1 Mini microcontroller board. The antenna side of the D1 needs to point to the side of the green screw terminal.

You can also plug in the ESP32 D1 clones.

You can however use other ESP32 boards but then you have to use Dupont wires to connect the ESP32 board to the base board. You can even use non-ESP type microcontrollers like Arduino and Raspberry Pi.

Loading the firmware

To load the firmware check the firmware installation instructions. When you load the firmware all default settings are already based on the S32.

Power options

To power the base board you have one options:

• USB power via the connector on the NodeMCU module.

When your boiler has a service jack, its possible to use the jack power by adding a back-type voltage regulator on J13. The input needs to be able to handle 12V and the output is 5V DC.

Voltages on the board

5 Volt DC

You need to power the board via the USB plug on the ESP board. The ESP32 board will then send 5V DC to the base board.

There is a high quality buck type voltage regulator on the board. This one is used to make 5V from either the DC barrel jack or from the service jack. When you use USB power then it’s not used. 5V is not used to power the base board itself.

3,3V DC

The entire base board runs on 3,3V. This is normally supplied via the 3V3 regulator on the NodeMCU-32S. If you do not use this microcontroller board, then you need to supply the base board with 3,3V.

5V DC is an input for the NodemCU-32S and 3,3V is an output from the NodeMCU-32S to the base board.

iRT modification

This board can also be modified so it can be used with iRT boilers. You need to remove R5 and place a 1.5MOhm resistor on R22 or R21. And use a Wemos ESP8266 microcontroller.