This is not going to be a thread that many people will be interested in. I might get some input, it might be me thinking out loud.

In this thread a few people have found that Daikin heat pumps aren't particularly accurate at setting temperatures, and that using an external temperature sensor would be useful. I'm going to look at the best way to do that, whether it's an automation, integration, AppDaemon app, or something else.

The only way we can really control the temperature is by by increasing or decreasing the temperature setting. Once you do that you lose the original setpoint, unless you save it in a new attribute. You would also have to detect the user increasing or decreasing the temperature and update the stored setpoint. That would mean using the existing controls in HA.

Another way to do this might be to create another HA climate entity for users to use, keep the user setpoint in there, and control the original HA entity using the automation. I don't know how practical this is.

It would be useful if this type of automation worked with multiple heat pumps, including those controlled using WiFi with a direct integration and those that use IR blasters such as Broadlink. The advantage of using the WiFi integration is you can get a little more information, such as the temperature that the heat pump thinks the room is, and whether it's currently actively heating / cooling / idle.

I've started writing a bit of Python code in AppDaemon to help my thinking around how this will work. The code currently detects the current temperature at the external sensor and reports whether the temperature from the external sensor is close to the setpoint, within a configurable tolerance.

Any thoughts on using a single or dual climate entities?

@allio I know you were interested.