[Feature request] Optional numerical output instead of ON/OFF

[tobimai]

I have Radiator valves which can be controlled by a 0-100 percentage, so it would be nice if the Thermostat could also output these values, as I want to control the TRV with an external Sensor.

So a numerical output, basically just the value which is then converted to PWM, would be very useful in my setup.

I don't know how difficult this is, or if you are interested in this feature but I just wanted to suggest it as the problem came up for me.

[ScratMan]

Hi, you may use a template to get the control_output attribute in HA
{{ state_attr('climate.salle_de_bain', 'control_output') | float }}

This is the output of the PID.
You will still need a dummy switch or script for the heater entity.

[tobimai]

That works, thanks

[cmug81]

Can you give an example of how to use the template in real world? I have floor heating valves also controlled via 0..100% and I would like to control their state with Home Assistant

[cmug81]

Can you give an example of how to use the template in real world? I have floor heating valves also controlled via 0..100% and I would like to control their state with Home Assistant

I think I understand. The idea is to create a new sensor, and then the value of that sensor comes from the state_attr.
Here is the sensor definition I created, which seems to work:

sensor:
  - platform: template
    sensors:
      valve_percent:
        friendly_name: "Heäting valve desired %-value"
        value_template: "{{ state_attr('climate.smart_thermostat_demo', 'control_output') | float }}"

[obelix05]

@tobimai : Can you tell me please which Radiator valves you are using? I'm looking for a percentage-controlled valve but only find the Eurotronic Spirit.
Thanks in advance.

[tobimai]

I have the Eurotronic valves.

Despite all the bad reviews they work perfectly for me with Zigbee2MQTT

[bluescoobie1969]

Hi tobimai! Very interesting! Today I also ordered a Eurotronic Spirit Zigbee TRV just because I want to start a similar project you do. I already tried the Moes ts0601 and the Saswell SEA802-Z01. Control loop in these TRV's is horrible, temperature sensor responds very slow and suffers a lot from direct radiator heat. Valve never reaches a stabil position which is gradually controlled (like my conventional Heimeier TRV you can feel radiator is partly warm) but keeps fully opening and closing. Additional you cannot use external temperature sensor, nor directly control the valve position. So would be great to make a real smart heating and close the control loop via HA and external temperature sensor! So great this numerical output from ScratMan's PID Thermostat is available! Opens the way for experiments! 1 big challange I already see is how to deal with the delay in the room temperature if the radiator starts to heat. Another issue is that I expect the water flow in the valve being highly non-linear with the valve position. Also the first small opening steps of the valve will cause (hardly) no water to flow, and near the end of valve opening no more water will flow even if the valve opens more. So maybe only use a specific part of the valve stroke? Food for thoughts! Maybe we can share our findings offline? Anyway good luck with this project!