TRV that partially opens more every few minutes

Hardware
1

HI, I hope my question isn’t crazy but I would like to ask for your help with this. I am really new in all this smart devices and I would like to try fix one issue in my apartment.

Every day 5am we get remote heat from heating company to our radiators. But because the radiators are cold it starts to crackle for few minutes and it’s really annoying.

I was thinking about installing smart valve, that will close the heat at 5am and then every few minutes it opens it for few percent. I would continue until it’s fully open.

Can you please recommend me some device that can do this with Home Assistant? I am looking on Moes, EVE and Tado but I am not sure if they can do this.

Thank you for your help and have a wonderful new year :smiley:

2

You could, instead of buying a device specially built for this purpose, is get any ordinary smart device that works with your TRV (i.e., outlet plug, etc) and write automation that steps it up in the manner you described.

I use similar automation to ramp up other devices in the same way.

3

Thank you, that is what I want to do, but I don’t kniw which device alows this. I read some of them do not allow setting the valve opening in percentage.

Any recommendations? Thank you

4

You are essentially setting the temperature. So set it to the lowest setting it supports (probably 5C) and then every few minutes you just increase the temperature.

  - repeat:
      sequence:
        - service: climate.set_temperature
          target:
            entity_id: climate.trv_valve
          data:
            temperature: >-
              {% set c = state_attr('climate.trv_valve','temperature')|float(0) %}
              {% set t = c + 0.1 %}
              {{ t }}
        - delay:
            minutes: 5
      until:
        - condition: state
          entity_id: climate.lower_house
          attribute: temperature
          state: "20.5"

Stuck in a repeat loop, with a delay of x minutes after the climate set temperature call. And an end loop condition

1 Like
5

No need to start with 5C.
The TRV will have a thermometer built-in, so start with that temperature and just set it to the next step higher, which will be the smallest adjustment you can do.
If your TRV have steps in 0.1 then you have it easy, but if it has steps in 0.5, as is often the case, then you need to do some modulus calculations.
Modulus returns the rest of a integer division and is often done with % as an operator, so 10%3=1 and 5%3=2

When working with temperatures, like 66.7, then 66.7%1 will give you the decimal .7 and then you can make an if the value is <5 then it should be .5 else it should be 1.
The selected value can then be added to the temperature rounded down to no decimals.

6

Thank you for all this help, but I still have few more questions :smiley:

  • When I go by setting the temperature, is the valve opening only slightly or to 100% and then back to 0%? Because I heard that some of the valves are very noisy, so I don’t want to switch one noise to with other.
  • Are there valves, where you can control the percentage of opening? Or are the valves so smart, that is the temperature in room is 18 degree and I want 18.5, it will not open it fully but just a little bit?
  • Do you have any experience with Moes, Sonoff or EVE valves or other that you can recommend?

Sorry for all my questions, but I am new to this and very interested.

Thank you