Home assistant integration w/ Daikin AC and Heatpump

[jonastemplestein]

Hi there, first off, thanks so much for this repo! And apologies for asking a tech support question here - it's just that nobody installing the equipment seems to know the answer

My builder is planning to fit a Daikin heatpump and AC system in my new house

AC:
Daikin FXNQ-A range internal units connected to Daikin RXYSQ external unit(s) in a VRV system arrangement

Heatpump:
Daikin Altherma range

I have the following requirements for my home assistant setup

• I only want one sensor unit in each room - this would be a multi-sensor with temperature, humidity, CO2, presence, etc
• I want to set a per-room temperature in Home Assistant that controls both the heatpump and the AC (ideally without also installing Daikin-provided additional thermometers)
• If Home Assistant is down, at least the underfloor heating should still work (but fine for AC to be broken)

Is this achievable at all via the P1/P2 bus integration?

[Arnold-n]

Page 10 of the installation manual shows different options for the Daikin controllers. You will then need exactly one Daikin remote controller per indoor unit (which will always work) and one P1P2MQTT bridge controlled from HA per indoor unit.

Do you have a separate system or unit for underfloor heating? The FXNQ-A units are all air units.

[jonastemplestein]

Thanks for the swift reply (and sorry for filing as an issue - it's not!)

So as far as you know, I should be able to use a non-Daikin temperature and humidity sensor in each room to control the Daikin AC units via P1/P2? Even though they are commercial units in VRV arrangement in multiple zones?

For underfloor heating, we're going to fit a Daikin Altherma heatpump

[Arnold-n]

The (wired) Daikin remote controller reports the local temperature and sets the desired temperature for the indoor unit, so there is no need for a further temperature sensor. The bridge allows to do it the same from HA. If you want to control humidity, you would need a separate sensor for that.

The Altherma is a separate system which can also be controlled from from HA via its own P1P2MQTT bridge if it is an Altherma 3.

[jonastemplestein]

Okay, thank you so much!

I think the idea would be to not have the daikin wired remote controller at all, and instead use home assistant to control the AC unit based on the temperature measured by the multi-sensor I already have installed. This seems like it should be possible?

And one final question (sorry): Does the Altherma 4 not work as well via P1P2 bridge for some reason?

[Arnold-n]

You do need the wired remote controller. The P1P2MQTT bridge communicates with that controller. It's also your back-up if HA is not available.

Altherma 4 has a different P1/P2 protocol.