Faikin Faikflow — Daikin Altherma Local Control Module

Local MQTT control for Daikin Altherma 2 and Altherma 3. No cloud, no Daikin account, no subscription. Works with Home Assistant and anything else that speaks MQTT.

Your Altherma already knows its flow temperature, its return temperature, how much energy it has used and how much heat it has produced. It just will not tell you without a cloud account.

The Faikin Faikflow wires into the P1/P2 user interface terminals inside your indoor unit and puts the whole system into Home Assistant over MQTT. Everything stays on your own network. There is no Daikin account, no ONECTA app, no cloud relay, and nothing stops working if Daikin changes its mind about an API.

Your existing wall controller keeps working exactly as it does now. The Faikflow sits on the same two-wire bus alongside it.

What you get in Home Assistant

Control

• Leaving water temperature setpoint, with heating mode
• Domestic hot water setpoint

Water and air temperatures

• Leaving water temperature (LWT)
• Return water temperature (RWT)
• Mixed water temperature (MWT)
• Domestic hot water tank temperature
• Room temperature
• Outside temperature

Energy, split out properly

• Energy consumed by the compressor, the backup heater and in total
• Energy produced for heating, for cooling, for domestic hot water and in total
• Which means you can calculate your real COP in Home Assistant, per mode, without a separate energy meter

System state

• Heat pump mode, heating mode and main zone status
• Domestic hot water active, and tank power
• Defrost active
• Water flow rate in litres per minute
• Pump running hours
• Error flag

Hybrid systems

• Gas boiler active, gas mode, and boiler running hours split between heating and hot water

It works with what you already use

MQTT is the point. It is the most widely supported protocol in home automation, and it means the Faikflow is not locked to any one platform.

• Home Assistant picks it up automatically over MQTT discovery. No YAML, no template sensors. Everything above appears as proper entities with the right device classes and units.
• The Home Assistant Companion app gives you full control on iOS and Android, with widgets, notifications and location triggers. For most people this is a better daily experience than the vendor app it replaces.
• Apple Home works through the HomeKit Bridge built into Home Assistant. That runs entirely on your own network, no cloud and no subscription.
• Google Home and Alexa both have well-trodden paths out of Home Assistant, either through Home Assistant Cloud or your own setup.
• Anything else that speaks MQTT can consume it directly, including openHAB, Node-RED, ioBroker, Domoticz and Homebridge. You are not obliged to use Home Assistant at all, though it is the path we support and the one that needs no configuration.

This is exactly the arrangement that makes the Faikin Faikout so flexible, applied to your heat pump.

The rest of the house

The Faikflow is for your Altherma and nothing else. It does not fit a split or a ducted system, and nothing else we make fits an Altherma. These are not alternatives to each other, they are different appliances.

Most people with an Altherma also have air conditioning somewhere in the house, and that is worth knowing about before you order:

• Ducted, Sky Air and VRV are the Faikin Ninja. That one does have Matter, so if you want to scan a code straight into Apple Home without going through Home Assistant, the Ninja does it.
• Wall-mounted splits are the Faikin Faikout.

All of it speaks MQTT and all of it lands on the same dashboard, so the heat pump, the ducted system and the bedroom splits end up in one place.

Why not the alternatives

Airzone's Aidoo needs an Airzone cloud account and the Airzone app. ESPAltherma is a do-it-yourself build onto the main system PCB rather than the thermostat bus, and it reads far more than it controls. The Faikflow is a commercial product that does local control, arrives pre-flashed and is supported by us.

Compatibility

Works with

• Daikin Altherma 3
• Daikin Altherma 2

Not this product

• Altherma HT (high temperature). The HT runs different firmware with a much smaller data set and is effectively read-only. We do not sell it as a control product. Contact us if you want to discuss it.
• Any Altherma that does not have P1 and P2 terminals on the X5M strip.

How to check in thirty seconds. Open the indoor unit and find the terminal strip marked X5M. Look for terminals 11 and 12, labelled P1P2 USER INTERFACE. If those are there, the Faikflow fits.

Note that this is not the same place as on a Daikin split or ducted system, where P1/P2 is on the REMOTE CNTRL block next to F1/F2 and T1/T2. On an Altherma it is lower down the X5M strip.

Send us your model number and a photo of the X5M strip and we will confirm it for you before you order.

Installation

1. Isolate power to the indoor unit, both indoor and outdoor.
2. Find terminals 11 and 12 on the X5M strip, marked P1P2 USER INTERFACE.
3. Connect the two module wires. The connection is non-polar, so either wire can go to either terminal. Wire is 24 to 12 AWG, 0.6 to 2.4 mm.
4. Restore power. There is no separate power supply to run.

Only two control devices are allowed on the P1/P2 bus, one Main and one Sub. Your wall controller is the Main and stays exactly as it is. The Faikflow joins as the Sub. If you already have a second device on the bus, such as an infrared receiver or a second controller, it has to come off first. Three devices on the bus causes phantom power-ons.

This is work inside a live appliance. If you are not comfortable opening the indoor unit and working on a terminal strip, get your installer to do this part. It takes them five minutes.

Setting it up

No app, and nothing to install. The setup is a web page served by the module itself, so any phone or laptop with a browser will do.

1. Power it up. The module brings up its own Wi-Fi network, named FaikinAC- and four characters.
2. Scan the QR code on the label with your phone camera and it joins that network for you. You can pick it out of your Wi-Fi list by hand instead if you would rather.
3. The setup page opens by itself. Choose your home Wi-Fi from the list and enter the password.
4. Enter your MQTT broker address, the port (1883 unless you have changed it), and the username and password if your broker uses them. You can do this now, or leave it and come back to it later once the module is on your network. It is the same page either way.
5. Press Save and Reboot. It tells you the IP address it has been given, then restarts.
6. Browse to that address whenever you want status, settings or a firmware update.

The status page tells you separately whether MQTT is connected and whether the module is talking to the heat pump, which makes it straightforward to tell a wiring problem from a network one.

Specifications

• Connection: two-wire P1/P2, at the X5M terminals inside the indoor unit
• Power: from the P1/P2 bus. No separate supply, no batteries
• Wi-Fi: 802.11 b/g/n, 2.4 GHz
• Reporting: MQTT, with Home Assistant auto-discovery
• Configuration: built-in web page, no app required
• Firmware: ships flashed and tested, updates over the air
• Cable: two-wire forked lead included, sized for the X5M screw terminals
• Enclosure: plastic

What this does not do

• No direct Matter pairing. An Altherma exposes roughly sixty entities and that does not map onto a Matter thermostat, so there is no code to scan straight into Apple Home the way there is on the Faikin Ninja. You reach Apple Home, Google Home and Alexa through Home Assistant instead, which is how the Faikin Faikout has always worked.
• No vendor app of our own, by design. The built-in web page is for setup and diagnostics. Day to day you use the Home Assistant Companion app or whatever dashboard you already have, which is a better app than we would ever write.
• No field settings. Installer-level configuration stays on the wall controller.
• Not a replacement wall controller. It runs alongside yours, not instead of it.
• Entities you do not have will not appear, or will read as unavailable. A system with no domestic hot water tank will not report tank temperature.

FAQ

Do I need Home Assistant?
It is what we recommend and support, and it needs no configuration because the module is picked up automatically over MQTT discovery. But this is a plain MQTT device, so openHAB, Node-RED, ioBroker, Domoticz and Homebridge can all read it directly if that is your setup.

Is there an app?
The Home Assistant Companion app, on iOS and Android, with widgets, notifications and location triggers. We do not ship an app of our own and we are not going to, because the Companion app is better than anything we would build and it puts your heat pump on the same dashboard as everything else in the house. Setup itself needs no app at all, just a browser.

Does it work with Apple Home?
Yes, through the HomeKit Bridge built into Home Assistant. That runs locally on your own network, with no cloud and no subscription. What it does not have is the scan-a-code Matter pairing on the Faikin Ninja, because sixty-odd heat pump entities do not fit a Matter thermostat.

Google Home, Alexa, SmartThings?
All reachable out of Home Assistant. Google Home and Alexa are the most direct, either through Home Assistant Cloud or your own setup.

Will it fight with my wall controller?
No. The module joins the bus as the Sub device. Your wall controller remains the Main and keeps full function. The one catch is that the bus only allows two devices in total, so if you already have an infrared receiver or a second controller fitted, that has to be removed first.

Can I still use the Daikin app?
If you have a Daikin LAN adapter fitted, yes, both can coexist. The Faikflow does not need it and does not talk to it.

Does it need internet?
Only to fetch firmware updates. Control is entirely local. Pull the internet and it keeps working.

Can I flash it myself?
No. It ships pre-flashed and configured for Altherma. Do not attempt to reflash it.

What if it does not work on my system?
Send it back. Our no-risk returns cover you, and we would rather sort it out or take it back than have you stuck with something that does not suit your heat pump.

I want the Matter pairing. Can I have the Ninja instead?
Not on an Altherma. The Ninja is for ducted, Sky Air and VRV air conditioning, and it will not control a heat pump. If you have both, buy both. The Ninja handles the aircon with Matter, the Faikflow handles the heat pump through Home Assistant, and they meet on the same dashboard.

Which Altherma do I have?
The model number is on the data plate on the indoor unit. Send us a photo of the plate and of the X5M terminal strip and we will tell you.