ET-P1101 – A DIY ESPHome Panasonic Climate interface

Getting the Panasonic Climate control off the cloud

Back in August 2021 we published an article about an esphome component for a esp32 or esp8266 based airconditioning/Climate Wifi interface. A great way to get your Panasonic Climate control off the Panasonic Comfort Cloud and into Home Assistant locally.  The only thing missing was a proper hardware solution, so we developed one and published the article here.

This SMD design perfectly replaces the original Panasonic Climate interface and even fits the original enclosure. The only disadvantage was that a SMD design is extreme hard to build yourself. We received a lot of requests to sell a pre-build interface. Those soon where sent all over the planet which cost us loads of time. That is not what we are about. We want to design hardware that you can easily build yourself, so we now finally publish our DIY version of the Panasonic Climate Interface. It’s easy to build, but still perfectly replaces a Panasonic DNSK-P11 or CZ-TACG1 WiFi interface.

How does it work?

Panasonic Climate units are usually connected to Panasonic’s Comfort Cloud using either a DSNK-P11 or a CZ-TACG1 WiFi interface.

CZ-TACG1

DNSK-P11

If you have one of these interfaces installed, you are unfortunate enough to be using the Panasonic Cloud service which sucks! Repeatedly having to log-in to your app and not not being able to control your Climate unit due to Cloud service outages are common issues. If you do not have one of these interfaces installed, you are likely not able to control your Climate units by anything else then the standard remote control that comes with the Climate unit.

The Solution

There is a solution to these problems. A custom esphome module allows you to connect Home Assistant to your Panasonic Climate locally. Remote controlling your Climate unit will be instant and no longer cloud dependent. Now the only thing needed is some hardware to act as the bridge between Home Assistant and the Panasonic Climate.

Design parameters

Our requirements:

• Must be able to connect to both the CN-CNT and the DNSK-P11 connector
  Must work as a DNSK-P11 or CZ-TACG1 replacement
• Preferably have the same size as the original interface
• Must support an external DS18B20 temperature sensor
• Must have a Micro-USB or USB-C terminal for esphome installation
• Enclosure must be readily available or 3D printable

So we designed a doughterboard PCB for a ESP8266 D1 mini sized module. After some testing we where unable to get this working stably. Modules differ from one Aliexpress or Amazon order to the other and this design suddenly stopped working after just reclacing the ESP8266 D1 Mini. After that we started testing the pin-compatible ESP32 D1 Mini. This worked reliably in all cases, but unfortunately the size of the ESP32 D1 mini is a lot wider and therefor not suited for our needs. We also tested a different design with different components, but that proved hard to build for a regular consumer. Finally we tested out initial design using the new ESP32 C3 Mini and that proved to work perfectly and fit within our size constraints.

PCB design

We where able to come up with a simple yet effective design using only 9 simple components. Add the ESP32-C3 Mini and a connector and you have yourself a working Panasonic Climate Interface for Home Assistant.

Schematic

PCB

Bill of materials

See below the list with the components you will need to build the Espthings ET-P1101 controller. A number of these items will not be sold in smaller quantities at AliExpress. We will try to use the same components as much as possible in other projects.

We would really appreciate it if you will use the links below to buy the components, since it will give a little bit of commission to us without any additional cost for yourself. These commissions will be used to cover some of the costs involved in the development of the design.

Putting it together

Like with all other projects, it is the easiest to start with identifying the components purchased as discussed in the blog post. After sorting the components and cleaning the PCB, start with the lowest components first. For this project, we advise to work in this order:

• DNSK-P11 header* (not required if you are attaching it to the CN-CNT to replace a CZ-TACG1 Wifi module)
• Diode
• MOSFETs
• Resistors
• Electrolytic capacitor
• ESP module headers (Use the hints in the soldering blog post!)
• CZ-TACG1 cable  (only If you are attaching it to CN-CNT connector)

* Use a very small soldering tip for the 1.27mm headers and use minimal amount of soldering wire. Make sure it melts and flows out siffuciently.

Once all components are soldered in place, perform a good visual check of all joints, and pay particular attention to possible solder bridges (unwanted solder connections between pins). Do not forget to clean the excess solder flux from the PCB using alcohol!

Finished module

In this case with both the DNSK-P11 header and the CN-CNT cable soldered. You only need one of both, depending on your climate unit!

Installation

DNSK-P11 replacement:

Original DNSK-P11 enclosure

Below a video on how to install the original CZ-TACG1 interface. The interface is different, but you’ll find clear instructions on how to open and close the unit. After taking off the enclosure, check your Climate unit for the DNSK-P11 enclosure.

Take the DNSK-P11 pcb out of the enclosure carefully, remove the black connector from the PCB and install your espthings P11 interface. Connect the interface using the original DNSK-P11 cable. The connector-lip needs to go downwords in the notch of the PCB, the flat part of the connector up.
Please be careful as the pins are tiny. If you use your brain in stead of brute force, you’ll be ok. 🙂

CZ-TACG1 replacement:

You can eiher replace the original CZ-TACG1interface, or if you have no Wifi interface installed yet and your Panasonic unit has the 5-pin CN-CNT connector, you are good to install the espthings.io Wifi interface.

CN-CNT connector

Below a video on how to install the original CZ-TACG1 interface. The installation of the espthings interface with the cable (option 5), is pretty straight forward.

Software

Create a new esphome device and use the following configuration example:

substitutions:
    devicename: "espthings-p11-diy"
    long_devicename: "ESPthings P11 DIY"
    pcb_version: "230902"
    
esphome:
  name: "${devicename}"
  name_add_mac_suffix: false ## if 'false' use different names/hostnames for each device!
  comment: "${long_devicename} ${pcb_version}"

esp32:
  board: esp32-c3-devkitm-1
  framework:
    type: esp-idf
  variant: ESP32C3

external_components:
  source: github://DomiStyle/esphome-panasonic-ac
  components: [panasonic_ac]
  
wifi:
  ssid: !secret esphome_wifi_ssid
  password: !secret esphome_wifi_password
  ap:
    ssid: "${devicename} Hotspot"
    password: qwe12345
    
captive_portal:
    
web_server:
  port: 80
  
logger:
  level: DEBUG

api:
  password: !secret esphome_api_password

ota:
  password: !secret esphome_ota_password

uart:
  tx_pin: GPIO7
  rx_pin: GPIO6
  id: ac_uart
  baud_rate: 9600
  parity: EVEN

switch:
  - platform: restart
    name: "$long_devicename Restart"
  
climate:
  - platform: panasonic_ac
    type: cnt    
    ### or change "cnt" into "wlan" for DNSK-P11 ###
    name: "${long_devicename}"
    vertical_swing_select:
      name: "${long_devicename} Vertical Swing Mode"
    outside_temperature:
      name: "${long_devicename} Outside Temperature"

Home Assistant lovelace config:

type: vertical-stack
cards:
- type: thermostat
entity: climate.your_p11_interface_name
- type: entities
entities:
- entity: select.your_p11_interface_name_vertical_swing_mode
- entity: sensor.your_p11_interface_name_outside_temperature

End result 🙂