Opentherm Gateway OTGW

The OpenTherm Gateway (aka OTGW) is a device that allows to view OpenTherm data from your thermostat and boiler or heating system.

Furthermore, it can be used to change settings, e.g. update the setpoint.

More information on the OpenTherm Gateway can be found on http://otgw.tclcode.com.

Hardware

The OpenTherm Gateway hardware can be ordered through online shops e.g. Nodo Shop.

Installing in Domoticz

After connecting the OTGW to the boiler, thermostat and to the network by Wifi or the Domoticz server by USB, the OTGW can be added to Domoticz.

Go to Setup - Hardware and select Opentherm Gateway USB or Opentherm Gateway with LAN Interface.

• Fill in an understandable name (eg Boiler Brandname or OTGW)
• For USB fill in the USB serial port name where it is connected (use the /dev/serial/by-id address or for older OS: do not forget to set Persistent USB device)
• For LAN interface enter the IP address and the port on which the OTGW device is connected.

After clicking on the Add button the hardware entry is created and Domoticz will connect to the OTGW and will add (after some time) 28 devices to the device list.

DHW: Domestic Hot Water system for supplying hot tap water.

CH: Central Heating

CH2: Second Heating circuit/system?

OTC: Outside temperature compensation.

GPIO: The OTGW has Input/output contacts that can be used for various operations, see documentation on http://otgw.tclcode.com.

Outdoor temperature and Commands

To select an outside temperature sensor to be used with OTGW, click on the Setup button in the Hardware list.

Select an outside temperature sensor that is already present in Domoticz or use the temperature sensor that is connected to the OTGW.itself.

When there are no physical outside sensors available, it is possible to create a virtual one by adding one of the Domoticz hardware Weather gateways (Buienrader, Darsky etc). These gateways will supply a virtual local outside weather temperature sensor that can be used by OTGW.

It is also possible to send commands to the Boiler or Heating system. See for more info http://otgw.tclcode.com/firmware.html#operation

Commands can also be set with Domoticz API json commands, for using in automation see link Domoticz API/JSON URL's

Supported OTGW firmware versions in Domoticz: 5.x (Domoticz stable 2021.1)

For questions and discussions about the OTGW, please use the Opentherm Gateway Forum on Domoticaforum.eu.

For questions and discussions on OTGW and Domoticz please use the OTGW subforum on Domoticz.com