eQ-3 Max Cube heating home automation

I have had the Max Cube, Radiator Thermostat, Wall Thermostat and Window/Door sensor, for about a year now, and this post will be about my current experience with the system.


Home Assistant has integration with Max Cube (More about further down)

There a also 2 other radiator thermostats and an “Eco Switch” button available. (You can use this when you leave the house to have a lower temperature)

You can read more about the eQ-3 MaxCube here
You can also connect the system to the MAX! portal – so you can control the system from a smartphone. I have not used this because you can not have a local connection to the MaxCube if you are connected to the MAX! portal.

My “Heating” history

Original when I bought my house it had standard radiator thermostats. I replaced these with the Danfoss RA-PLUS thermostats – these have a weekly program, so you can have a lower temperature at night (or whenever you like).  After using these for several years I wanted something smarter:

At the beginning I was looking for something using z-wave, but the price is about 3 times the cost of the Max Cube system. I also found was several opensource implementations of API’s used to connect to the MaxCube (The interface is not documented from eQ-3). So I decide to try the MaxCube system, because it is cheap. I have 7 Radiator thermostats, 1 Wall Thermostat, and 1 door/window switch and the MaxCube lan gateway – the total cost was 1478 DKr

The Radiator Thermostat

There are 3 different models and this is the “basic” model (The least expensive of the 3). The other 2 models can be programmed with weekly timers without the MaxCube gateway – so I don’t see why you would want these if you have the gateway. The basic model is also the best looking of the 3 (Would have been even better if the adapter was also white, and not gray)

You can adjust the temperature directly on the knob (or you can lock it in case you do not want someone to accidentally do that)
It is powered by 2 AA batteries – battery life should be 2 years (I have not yet changes my batteries)

At the beginning I did have some problems with the thermostat reporting errors after a descaling, done once a week. (This operates the thermostat between max and min positions, to keep the valve i good condition). The main issue here is the adapter for the Danfoss valves. If you tighten the adapter too much the threading will be too small and the thermostat can skip the threading.

 The door/windows switch is used to lower the temperature when the door/window is open. I only have one of these and I primarily bought this to test it. (I have IHC magnet contacts in my doors and windows where needed)

It is powered by 2 AA batteries, and battery life is expected to 5 year (yet to bee seen and of cause depends on the usage)

I would like to have “threshold” feature where the sensor has to be activate more the X seconds before the temperature is changed. If I walk out of a door I can hear the Radiator Thermostat regulating almost immediately. That could probable give better battery life, because I assume operating the valve motor in the Thermostat is power expensive. If a door is opened and closed again shortly after there is not need for the thermostat to do anything.

The wall thermostat works together with the radiator thermostat and allow you to control the heating from a central place in a room. It also measures the temperature and send this to the radiator thermostat or MaxCube gateway.

As the other devices it is powered by 2 AA batteries – battery life should be 2 years


The MaxCube has a Ethernet connection and is powered by a 5v usb power supply. (The Ethernet connection is on the top, and this is a bit annoying)

You connect to the gateway using the software from Eq3. The software can find the gateway automatically on your network. The UI is web based the software runs as a local hosted web service.

The Radio frequency is 868,3MHz, and I my small house there is not connection problem. It can take some time for the devices to connect and update but it works fine. (I think I have read somewhere, the devices are connected in a mesh network, but I could not find this again)

The integration into Home Assistant is about 1 your old, and it does not look like there has been any changes/features since the original. Each Radiator Thermostat and Window/Door switch are integrated as a device in HA, and you can control the temperature and mode from HA. The integration uses polling (with an non-configurable interval of 1 minute), so you should not expect the Window/Door switch to react instantly.

A big problem:

Occasionally with an interval of several weeks my MaxCube is reset to factory defaults, and I have to setup all devices again. (This has happened several times for me, and is really annoying). This appears to be a hardware problem with the MaxCube, because others have had similar problems in OpenHab. If you don’t connect it to HA there is not problem.

I have made a post about this on the HA forum but nobody has yet found a solution. Making the polling interval longer should help, so for now I have changed that in the MaxCube code (This is not yet available as a configuration parameter). I have made the polling interval 5 min, and have not had a reset since I changed this. Another solution could be to keep the connection*) to the MaxCube (Something you can configure in OpenHab), but this is not as easy (Will require changing the python maxcube-api a lot). Depending of this “testing” a more permanent solution is needed. (Changes you make to the HA code will be overwritten each time HA is updated, so for now I have just copied it to the configuration folder as a custom component that will override the build in maxcube component).

*) The MaxCube only allow one connection so keeping the connection will not allow you to connect using other software.


The MaxCube heating system is cheap and regulates the heating fine. The software is OK, but not fantastic. The fact that you can connect from misc home automation systems is great (and for me the reason to have this system). This also means you only have to use the included software when setting up the system.

The problem about the system resetting to factory default is terrible – and if I do not find a solution this is a deal breaker in the long run.

If anybody have found a solution to this problem please let me know in the comments below. Or if you have another heating solution that works well with Home Automation systems



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