Relying on 4 nvme drive for low power isn’t ideal as nvme drive needs about twice more power compare to sata SSD.

You can use an helper to toggle from one to another and use an automation to trigger it (or a simple switch on your dashboard).

But if I were you, I would use a community add-on as dual AC isn’t a niche, I guess it will keep being updated in future. I’ve been using some community add-on for a couple of years and none have been dropped til now.

Instead of using a community add-on, you can create two generic thermostat. https://www.home-assistant.io/integrations/generic_thermostat/

Don’t have the max version but I believe they shared the same extruder as cr6 se

This video shows how to put it back together https://www.youtube.com/watch?v=adVzvhmIKZM

And they are several option to replace extruder. Cheap one are the same compatible of ender 3 like this one at 4€ https://a.aliexpress.com/_EyXIa19 but you will have to print a raiser for the filament sensor

here is my config yaml for climate. added hint for your case but i never had heat pump, does your heat pump only heat or does it also cool? exemple here is ok if only heat. If yours heat/cool, try some of the hacs thermostat addon. A quick search led me to this https://community.home-assistant.io/t/generic-thermostat-switch-between-heating-and-cooling/420053 which point to https://github.com/swingerman/ha-dual-smart-thermostat but i know they are more hacs addon for thermostat, you may need to search which is good for your use if the one above doesn’t suit your needs

climate:
  - platform: generic_thermostat
    name: Thermostat Chambre (Riscaldamento)
    heater: switch.radiateur_chambre (device to toggle your heat pump)
    target_sensor: sensor.sonde_chambre_temperature (your temp sensor)
    min_temp: 12
    max_temp: 21
    ac_mode: false
    target_temp: 19
    cold_tolerance: 0
    hot_tolerance: 0.1
    min_cycle_duration:
      seconds: 300
    keep_alive:
      minutes: 3
    initial_hvac_mode: "off" (set this to heat if you want it to be active when HA start/reboot)
    away_temp: 12
    precision: 0.1

Unless you want some specific schedule, there is no need for automation, add config to yaml and it is good to go

Just use generic thermostat https://www.home-assistant.io/integrations/generic_thermostat/

Smart home junkie just made a video about it https://youtu.be/o3yZWD_sFIE

Will try that soon