HVAC - Controlling Dampers via Advantage Air Zone Station II

Hardware
1

Hi,
I am trying to automate my ducted AC system.

System Description (current state):
It is a Fujitsu AC system, split into 4 zones.
Temperature and Flow control is done via the Fujitsu wired control panel (UTY-RNRT) https://www.fujitsugeneral.com.au/commercial-products/controllers/details/uty-rnrt

The system has 4 zones, controlled by 4 damper motors. These are controlled via an Advantage Air Zone Station II Control Box. Selection of the zones (opening/closing of the dampers) is peformed via the CSP2 control panel, which allows the zones to be actiavted/deactivated manually.
Picture of the Zone Stations II is below. Will post control panel and internals later.

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Speaking to my AC guy, he has offered to sell me an Advantage Air My Air control system, including tablet touch panel for some $3000+…
Not keen on this, as I want to keep it simple and automate via HA.

Desired System
I want to use HA to automate the system in two steps. First use the Fujitsu AnywAIR WiFi interface to control the AC unit (heat/cool mode, temperature, fan speed). Second automate zone selection based on temperature in various rooms (I already have several Z-wave room thermostats).

Ideally, I would keep the wall controller for zone selection, and include a switch to toggle between auto and manual control.

Advice/Help needed
I am considering the following solutions:
Option 1:
The Zone Station II includes a second RJ45 port which can be used to connect a second zone selection panel (refer to manual https://specialisedair.com.au/wp-content/uploads/2019/12/ZONE-STATION-II-TECH-DATA.pdf.
I Would like to connect a micro-controller here, that emulates the control panel and that can be controlled from Home Assistant? (I.e. almost like a smart button pusher)

Option 2:
Replace the Zone Station II with a set of z-wave controlled general purpose relays (e.g. Zooz Universal Relay) to drive the dampers.
However, here I would loose the state indicators on the wall panel and the option for manual control.

Has anyone on here tried to emulate one of these push button control panels in order to automate a Zone Station 2?

Are there other straightfoward options that I am ovelooking?

I am keen to try and implement option 1.
However, I would need some advise on how to start reverse engineering the communication protocol to the wall panel.

Hopefully, someone on here is able to help.

Thanks
Dingo

2

Zone controller

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3

Zone Controller Internals:

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4

Then you need to find out the communication protocol.

What about wiring Esp dev board to the button contacts just to emulate button presses? What’s the voltage across the button? Common on the right side is gnd?

5

Did you manage to reverse engineer the software? If not I think I have a solution.

6

I would just replace the controller with a homemade ESPhome setup. Super easy.

7

Not so with 24v AC Damper motors. Either way the ZSII controller is RS485 compliant. I am currently waiting on my RJ45 to RS485 adapter to arrive, and I’ll be reverse engineering the protocol. If something aint broke don’t fix it.

8

An ESP controlling relays which switch the 24Vac is easier.

9

agreed but a lot of individuals want something that is plug and play. ESPhome and relays require a buttload of wiring. I’m trying to figure something out that just plugs in :slight_smile:

10

I’ve managed to workout the protocol. Let me know if you’re interested and I’ll provide you the ESPHome yaml config.