Help for a newbie - create a card that will turn on my HVAC fan for a configurable amount of time

Configuration
1

I am relatively new to HA and trying to figure something out. I have searched around, but not found a close enough match. Perhaps somebody would be kind enough to point me in the right direction or to give me some suggestions.

I have a carrier HVAC which I have integrated into HA. I would like to have a menu driven option that would change the fan operation. I typically set it to “auto”. Under certain circumstances, I would like to have it on a constant run for a configurable amount of time. For example, I would like to be able to choose to run it for 15 minutes, after which it would resume to “auto”. The time should be something that is selectable. It would also be nice to be able to select the fan run speed (high, med, low) at the same time.

Thank you in advance for the assistance.

2

Here’s a theoretical example:

Create two input selects (in yaml or from the helpers UI).

input_select:
  fan_speed:
    name: Fan Speed
    options:
      - High
      - Med
      - Low

  fan_run_time:
    name: Run Time (Minutes)
    options:
      - 5
      - 10
      - 15  # add as many as you want

Add those helpers to a card in your dashboard.

Create an automation to monitor them for changes and to action them when they do change:

- triggers:
    - trigger: state
      entity_id: input_select.fan_speed
      not_to:
        - unknown
        - unavailable
    - trigger: state
      entity_id: input_select.fan_run_time
      not_to:
        - unknown
        - unavailable
  actions:
    - action: climate.set_fan_mode
      target:
        entity_id: climate.your_hvac_here
      data:
        fan_mode: "{{ states('input_select.fan_speed')|lower }}"

Create another automaton to revert to auto mode after the elapsed time:

- triggers:
    - trigger: state
      entity_id: input_select.fan_speed
      not_to:
        - unknown
        - unavailable
      for: 
        minutes: "{{ states('input_select.fan_run_time')|int }}"
    - trigger: state
      entity_id: input_select.fan_run_time
      not_to:
        - unknown
        - unavailable
      for: 
        minutes: "{{ states('input_select.fan_run_time')|int }}"
    - action: climate.set_fan_mode
      target:
        entity_id: climate.your_hvac_here
      data:
        fan_mode: "auto"

Note: these helpers and automations will probably require some adjustements. Go to Developer Tools → States and look at what your actual fan speeds are listed as, then post them here. e.g. here are two of mine:

brave_screenshot
brave_screenshot1063×444 37 KB

You may also need some further actions if you want to use this when the HVAC is off (i.e. turn it on first).