General Information
Temp. Outside9,2 °C
Temp. Inside22,7 °C

Usages for today
Gas0,59 m3
Power7,6 kWh
Water225 L

HA Statistics
Devices 292
Device values 1723

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Opentherm Gateway
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Since November 2012 I am monitoring and controlling my central heating with a DIY OpenTherm Gateway. With a PCB, 2 hours of soldering and a total costs of approx. 40 Euros you've got a device that can decode the OpenTherm communication between your thermostat and boiler system.

But there's more - the OpenTherm Gateway also enables you to override the thermostat setpoint, control DHW (Domestic Hot Water) operational parameters, set the clock and obtain lots of additional information from the boiler.

I'm using the OpenTherm Gateway mainly to override the thermostat setpoint. For example, when my system detects that there's nobody at home it can lower the thermostat setpoint and automatically raise it again when human presence is detected again - the same way I power off some devices in our house in order to save energy.

Below is a part of the information that can be obtained with the OpenTherm Gateway. For more information about the OpenTherm project see my weblog .

Real-time OpenTherm information
Socket Connection State ?
Central heating mode No
DHW mode -
Flame -
Modulation level - %
Thermostat setpoint - °C
Thermostat override setpoint 0.00 °C
Room temperature - °C
Flow temperature - °C
Return temperature - °C
Water pressure - bar