Control Junkers gas heating (1-2-4 interface) with Home Assistant

[JKL_9028 (Kuba)]

@niesamowitysmyk is there a possibility that you can help with the assembly and first run? I ordered the PCB, but I’m not sure about what components I need. I’m not really experienced with this.

[derpuma]

Is it possible to use this with a ZWR 18 or ZSR 18?

[Stabe]

Hi, I am unable to configure the yaml for the Dallas DS18B20 temperature sensor. Can anyone advise me?

[Stabe]

Can someone advise me how to modify the yaml for homeassistant, due to the change of template function in homeassistant?

[phier (john)]

Hello there,
found that project and its super cool!

Is there any update on that?
How do you guys monitor temp in the rooms and also valves?

How that project/module measure room temp and based on that does “modulation”?
What precisely is mentioned 1-2-4 interface? Is that 24V PCB to which controllers as Junkers CW/CR100 are plugged?

Still not clear on that Board → EMS device compatibility – BBQKees Electronics what is it purpose?

Thank you!

[Godmag]

This blog post above helped me to make a small variant because I’m too inexperienced for the advanced version of Strooom.

I wanted to keep the original thermostat so I took the three cables from the heater connected it to a shelly 1 plus and from there to the thermostat. Advantage is it’s possible to operate the heating with the thermostat directly in case my home assistant server crashes/breaks.

Small flaw: The thermostat will report an error on its display when the heater is turned off via shelly because it thinks there is no heater connected. Please see photo below. Doesn’t do anything to functionality though.

Made some photos of my solution. The cable management is not the slickest way but it also looks kind of nerdy so Im fine with it.

[vajdum]

@phier

How do you guys monitor temp in the rooms and also valves?

I have:

• a stroom smartTherm (but its not very useful to me, because i nearly always use heating level 1%, so no advantage to the shelly)
• a gasmeter where i can see the boiler heating using a magnetometer, which shows gas usage also between the counting ticks.
• some bluetooth TRVs and thermometers.
• 2 automations to switch the boiler on/off regarding of valve opening state and temperature, different conditions per room.

Our boilers power is too much for our heating need, so i try to minimize the burner switching on/off all the time.
F.e. the most used room needs valve 50% whereas the TV room only used in the evening needs at least 70% for the boiler to be switched on.
This way most TRVs on rooms with warming need are at least partially open, so the warm water has a change to be used rather then circulating in the pipes only and heating is way of synchronized.

Triggers for the ON automation are too low room temperatures, water temperature below 20°C and open TRVs.
Trigger for off automation are the burner being off for 3mins, TRVs closed and temp. in the most used room too high.

[JKL_9028 (Kuba)]

I ended up using a 24v to 5v converter to get the power to ESP from Junkers. No additional power sources needed this way.

I’m testing it now.

I think I will mount it next to the heater and use completely separate temperature sensor for controlling it.
It would be nice to use external thermostat like for example this one: LINK to be able to control it. But it needs to be figured out I guess.

I’m also thinking about designing a 3d printed case for it.

[vajdum]

@jwm, do you have an esphome yaml snipped for the manual on/off button to switch the heating switch?

[jwm]

I don’t understand your question sorry. Maybe this helps? Button Component — ESPHome

[vajdum]

i tried to install a button to manually switch heating on/off. I was asking for your yaml to switch the heating if the button is pressed.
My button had not worked due to false wiring (between tx + gnd as rx is occupied by dht22).
Now its wired to A0 + 3.3V on J3 (with an additional 2.7k resistor) in place of light sensor and i use this to get an Button on/off

 # manual switch for heating (internal)
  - platform: adc
    pin: A0
    name: ${project_name}_adc_button
    id: manual_heating_internal
    internal: True
    update_interval: 5s

# manual switch for heating
  - platform: analog_threshold
    name: ${project_name} Button
    sensor_id: manual_heating_internal
    threshold: 0.2

[damyzster (Damian)]

Hi Godmag I really like the way you figured it out. Could you share a pic how did you make connection between shelly and thermostat ?

[scharc]

I followed your lead an got the same setup. Thanks.

Here is a poto for anybody out there how to set it up:

In simple terms:

1. hook the shelly up with the 24V+ and GND in parallel to the control box
2. connect the PWD / SIG to the O
3. bridge the GND to the I

Now you can GND the SIG bus and that will tell the heater to stop heating.