Home Assistant automation to turn on/off the main units of the air conditioning system depending on whether the split units are working or not (just to save a little bit watts-hour)

The Mitsubishi Electric MXZ-3F68VF2 is a split type air conditioner system consisting in a central unit and up to 3 split units, and it can be complemented with an internet device to allow the management from mobile devices and the like thanks to the MELcloud portal

Home Assistant integration with MELcloud can be found here. The integration provides entities that can be utilised in the thermostat card easily.

So, for the whole solution, we just need one thing more: one smart switch. In this case we are using a Shelly PLUS 1PM device which has power metering sensor in it and other sensors such overheating and more.

I’ve observed that, when no split is functioning, the central unit power consumption ranges between 10 and 20 watts approx. That means, considering an usage of 8 hours per day, around 100 kwatts-hour per year, which may cost around 30€ at current prices including taxes.

So, why not create integrations that switch the main unit on and off depending on if at least one of the splits have been activated?

switch on automation

So, for the switch on operation, we check every minute for the state of the entities that tell us if someone activated a setting such as cooling, heating or whatever.

alias: AUTO-INT-CLIMASUR-ON
description: ''
trigger:
  - platform: time_pattern
    minutes: /1
condition:
  - condition: or
    conditions:
      - condition: template
        value_template: '{{ not is_state(''climate.hab_principal'', ''off'') }}'
      - condition: template
        value_template: '{{ not is_state(''climate.salon'', ''off'') }}'
      - condition: template
        value_template: '{{ not is_state(''climate.azul'', ''off'') }}'
action:
  - type: turn_on
    device_id: fd8f86b6a3860477e6e931f53299fdb0
    entity_id: switch.int_climasur_switch_0
    domain: switch
mode: single

switch off automation

In this case, every 30 minutes we check for the state and, if all states are off, whe switch off the smart switch.

alias: AUTO-INT-CLIMASUR-OFF
description: no split running?
trigger:
  - platform: time_pattern
    minutes: /30
condition:
  - condition: and
    conditions:
      - condition: state
        entity_id: climate.salon
        state: 'off'
      - condition: state
        entity_id: climate.azul
        state: 'off'
      - condition: state
        entity_id: climate.hab_principal
        state: 'off'
action:
  - type: turn_off
    device_id: fd8f86b6a3860477e6e931f53299fdb0
    entity_id: switch.int_climasur_switch_0
    domain: switch
mode: single

DISADVANTAGE NOTE: As the main unit is disconnected, splits units doesn’t have energy, so the temperature and rest of the sensors stop sending data to MELcloud portal

That’s all, hope it helps!! 🙂