Tuya-thermostatic-valve

automation documentation for better temperture control, with an external temperature probe / window contact

prerequisites

• Home Assistant (2021.2.0 at the time of writing)
• Properly setup Zigbee2MQTT plugin (or similar)
• properly installed
  • TuYa TS0601 thermostat
  • Aqara Temperature Sensor (or similar)
  • Aqara window contact sensor (or similar)
  • TuYa TS0121 plug (or similar) for any electrical heat source
• latest thermostat firmware
• thermostat settings:
  • Make sure the build-in "window detection" is off
  • Set minimal temperature to 1°C
  • Set maximum temperature to something high, like 35°C
  • Set hysteresis to 0.5°C (default is 1.0°C)
  • Make sure the valve control type is set to "PID"
  • there's no need to set any 'local temperature correction' - this value won't be touched, but has no effect on the automation.
• Enable the OpenWeatherMap integration(or similar) to get an outside temperature

recommended mods

• Attach a 3 V power supply at the pcb to avoid fast battery drainage due to larger/more often valve operation, see power supply mod

limitations

• Can only set one temperature, if you need a week/daily cycle, you need to modify the automations or just modify the slider
• Can only work with an good external temperture probe, which is properly installed, see installation temperature probe for help
• there's no "get the heat on fast" for a very cold room (but the TRV should turn on the heat pretty quickly anyway, since there's a high temperature differential)
• there's no "boost mode" if you feel very cold and just want a short increase in temperature. Workaround: feel free to use just your own automation for this, to create a button which increases the target temperature for a while and then turn it back to the previous setting. You can also still use the boost mode on the TRVs
• The controls at the TRV are completely useless. Every change there will be overwritten on the next change by the automation

helpers

Create the following helpers:

Warning: Only manually modify the last two manually, the rest is to store the status of the automations.

expected naming of sensors/actuators

• climate.radiator_valve_kitchen for the thermostat
• sensor.power_plug_airfryer_power and sensor.power_plug_exhaust_hood_power for heat source detection
• sensor.temp_sensor_kitchen_temperature for the temperature probe
• binary_sensor.window_sensor_kitchen_contact for the window sensor
• sensor.openweathermap_temperature for an environment temperature sensor

statistics sensors

• sensor.derivation_filtered_temperature_kitchen:

  sensor:
  - platform: derivative
  name: "Derivation filtered Temperature - Kitchen"
  source: sensor.kitchen_filtered_temperature
  time_window: "00:03:00"

• sensor.kitchen_filtered_temperature:

  sensor:
  - platform: filter
  name: "Kitchen filtered temperature"
  entity_id: sensor.temp_sensor_kitchen_temperature
  filters:
    - filter: time_simple_moving_average
      window_size: "00:01:00"
      precision: 2  

• sensor.temperature_statistics_24h

  sensor:
  - platform: statistics
  name: 'Temperature statistics 24h'
  entity_id: sensor.openweathermap_temperature
  max_age:
    hours: 24
  sampling_size: 86400
  precision: 2

heat source detection

This automatisms is an example how to detect a running stove or a heat generateing device early, to avoid running the heat at the same timewhile those devices are running. This way you can avoid venting the room in some cases, when it would become too hot otherwise.

Detection with just the temperature probe is too delayed in most cases to help much.

heat mode automation

This automatisms shuts the valves in all scenarios where this is commanded by other automatisms or by the user.

'heat rising too quickly'-detection

This automatism can detect sudden rises in temperature, like if someone is taking a shower in a room, does cooking or has an electrical device on, which generates a lot of heat. It can also detect a haywire reaction of the valve opening too long which would lead to an overshooting of the set temperature. This is important if you vented the room down several degrees and you're trying to heat it up again. This automatism will shut the valve to give the radiator more time to spread the heat in the room.

switch the heat mode for the window and heat sources

Those automatisms switch the input_select-heat modes according to the heat source and window sensors.

thermostat controller

The main temperature controller automatism. Gets triggered by some events pretty regularily, but the delay at the end and the single execution makes sure it only runs once a minute at most - to avoid too many valve operations.

The first condition in the choose makes sure that if the temperature is within -0.5°C the heating is reduced properly by the valve. If not the valve is closed and the valve's automtion restarted at 0%, which ususlly let it open again slowly - if neccessary - on it's own.

When it's 30% or below it's ususally already detecting the approached set temperature right, and will close soon.

The second condition in the choose just updates the set temperature on the valve (relative to the measured temperature of the valve itself) as long as the set temperature isn't reached.

a simple weather detection

This detection tries to detect two different type of weather scanarios:

• Hot days, where you like to get some cool air into your house to chill it down in the night. You don't want no heating to turn on on those days, even in the night.
• Mixed bag weather, like when it's around 20°C and bit cooler in the night, but you don't want your central heating system to turn on to inrease the temperature in all rooms by say 1°C.

home assistant startup

On startup all valves will be closed and the heating mode will be set to the internal value default to make sure the automatism has a defined starting point.

valve maintaince

In summer the valves usually get never moved, this automation moves the valves once a day to avoid that the valves get sticky or stuck.