bwalink

This is a docker container for https://github.com/ccutrer/balboa_worldwide_app that supports a remote serial to IP device or host running ser2net, socat or ESPEasy serial server.

There are 3 components to this solution:

• A serial to IP device
• Serial to MQTT which this docker image hosts
• MQTT to Home Assistant

Installation and configuration of MQTT are beyond the scope of this project as there are a plethora of good articles on setting up an MQTT broker.

Table of Contents

• bwalink
  • Disclaimers and Legal Stuff First
  • Serial to IP Device
    • Elfin-EW11A-0
      • Setup
      • Connection Cable
      • EW11 Interface Conversion Cable
  • BWALink Docker Setup
  • Home Assistant Configuration
    • Switches
    • Sensors
    • Numbers
    • Input Select
    • Automations to support the selectors

Table of contents generated with markdown-toc

Disclaimers and Legal Stuff First

As an Amazon Associate I earn from qualifying purchases. I get commissions for purchases made through links in this post. Most hot tubs are fed 240v and are capable of delivering 50-amps of current = 12,000 W so... electricity is dangerous and can cause personal injury or DEATH as well as other property loss or damage if not used or constructed properly. If you have any doubts whatsoever about performing do-it-yourself electrical work, PLEASE do the smart thing and hire a QUALIFIED SPECIALIST to perform the work for you.

NEVER WORK WITH LIVE VOLTAGE. Always disconnect the power source before working with electrical circuits.

Serial to IP Device

Elfin-EW11A-0

I've had great success with the Elfin-EW11A-0 from Hi-Flying Technology. It's a simple $24 RS-485 to WiFi device that takes an input voltage of 5-18VDC, has a web interface for remote admin and an external antenna.

Setup

• Supply 5-18VDC to the 2 middle screw terminals as shown below to power up the unit
• Connect to the wireless network named EW11_D650
• In your browser, navigate to 10.10.100.254 and login with username: admin password: admin
• Go to the system settings page and configure the WiFi Settings to match your network

Value	Setting
WiFi Mode	STA
STA SSID	your wifi SSID
STA KEY	your wifi password

Optionally You can setup a static IP address using the LAN Settings section. Just remember to turn DHCP Server to Off.

• Click Submit
• Go to the Others page and click Restart
• Determine which IP the device acquired from DHCP or use the static IP you assigned and enter it in your browser
• Login with username: admin password: admin. This is a good time to change those and will only affect the web admin.
• Go to the Serial Port Settings section and configure as follows

Value	Setting
Baud Rate	115200
Data Bit	8
Stop Bit	1
Parity	None
Protocol	None

• Click Submit
• Go to the Communication Settings section and configure as follows

Value	Setting
Name	netp
Protocol	TCP Server
Local Port	8899
Buffer Size	512
Keep Alive(s)	60
Timeout(s)	0
Max Accept	3
Security	Disable
Route	Uart

• Click Submit
• Go to the Others page and click Restart

Connection Cable

You'll need an ATX Molex Micro Fit Connector to connect to the communications port of the Balboa equipment. I also recommend:

• Silicone coated wire optional if you already have wire but much easier to work with
• Heat Shrink Tubing or Electrical Tape
• Soldering Iron and solder
• Good wire strippers/cutters
• Multimeter

My hot tub had a small Y-Cable hanging outside of the control box that you can plug into for power and to get to the RS-485 communications of the tub. If you don't have this cable, you can likely plug into the main control board if it has the same outlet type. This should be the same type of connector that goes to your control panel.

Note that the tab is on the left of the connector

The connection is an ATX Molex Micro Fit Connector 4Pin (no, not the same as your old ATX power supply, I know, I tried too). Cut the one you ordered in half since you'll be making your own cable. Strip the ends of the ATX Molex Micro Fit connector. Be careful not to short anything and plug that into your tubs Y-cable or J33/J45 port. Confirm and tag the wires for +V, ground and RS-485 A/+ and B-, they should match the image.

Disconnect the cable and solder ~36-inches of Silicone coated wire onto each of the ends using the color that corresponds to the pin. Use some Heat Shrink Tubing or electrical tape to protect your soldered connections. I suggest crimping some 22AWG ferrules to the ends of those cables or you can just tin them and be careful.

Color	Pin/Wire
Red	DC +
Black	Ground
Yellow	RS-485 A/+
Blue	RS-485 B/-

You can now connect the wires as show in the image below to the screw block at the end of the EW11 interface cable.

NOTE: You can disconnect the terminal block to make it easier to work with.

EW11 Interface Conversion Cable

Plug everything in and confirm you can access the web interface of the EW11.

I drilled a small hole in the bottom of the hot tubs plastic media device enclosure, routed the cable in and stashed the EW11 in there. The media pocket has the added benefit of being unshielded, unlike the rest of the tub which has foil insulation.

BWALink Docker Setup

Installation and configuration of Docker and docker-compose are beyond the scope of this project as there are a plethora of good articles on setting up Docker.

• Download or copy the docker-compose.yaml file and modify the MQTT_URI and BRIDGE_IP to match your set up
• Run docker-compose up -d and let Docker do its magic.

NOTE: MQTT_URI must be properly escaped, e.g. mqtt://useename:pa##word@10.1.10.2 would need to be mqtt://username:pa%23%23word@10.1.10.2. See https://www.urlencoder.org/ for details.

Alternatively, you can execute docker run --rm ghcr.io/jshank/bwalink:latest -e MQTT_URI='your_mqtt_uri' -e BRIDGE_IP='your_ew11_ip'

If everything went well, you can subscribe to the homie/# topic of your MQTT broker and should see something like this:

homie/bwa/$homie 4.0.0
homie/bwa/$name BWA Spa
homie/bwa/$state ready
homie/bwa/$nodes spa
homie/bwa/spa/$name BWA Spa
homie/bwa/spa/$type CL501X1
homie/bwa/spa/$properties priming,heatingmode,temperaturescale,24htime,heating,temperaturerange,currenttemperature,settemperature,filter1,filter2,pump1,pump2,pump3,light1,circpump
homie/bwa/spa/priming true
homie/bwa/spa/priming/$name Is the pump priming
homie/bwa/spa/priming/$datatype boolean
homie/bwa/spa/heatingmode ready

Run BWALink as a Home Aassistant Addon

If you use Home Assistant, you don't need to run your own docker setup - you can run it as an addon.

• Under /addons, create a new directory called bwalink. More info: Tutorial: Making your first add-on
• Copy the full content of ha-addon into the new directory
• Open the Home Assistant frontend
• Go to "Settings"
• Click on "Add-ons"
• Click "add-on store" in the bottom right corner.
• On the top right overflow menu, click the "Check for updates" button
• You should now see a new section at the top of the store called "Local add-ons" that lists your add-on!
• Click on your add-on to go to the add-on details page.
• Install your add-on
• Adjust configuration
• Start your add-on
• Click on the "Logs" tab, and refresh the logs of your add-on, you should now see the details in your logs.

Home Assistant Configuration

If you have MQTT Discovery enabled, Home Assistant will get a new BWA device along with all of the discovered sensors and switches for the spa. Otherwise, you'll need to manually create them as follows.

Switches

  - platform: mqtt
    name: "Hot Tub 24hour Clock Mode"
    state_topic: "homie/bwa/spa/24htime"
    availability:
    - topic: "homie/bwa/$state"
      payload_available: "ready"
      payload_not_available: "lost"
    command_topic: "homie/bwa/spa/24htime/set"
    payload_on: "true"
    payload_off: "false"
    icon: mdi:wrench-clock
    
  - platform: mqtt
    name: "Hot Tub Pump 1 (Lounge)"
    state_topic: "homie/bwa/spa/pump1"
    availability:
    - topic: "homie/bwa/$state"
      payload_available: "ready"
      payload_not_available: "lost"
    command_topic: "homie/bwa/spa/pump1/set"
    payload_on: "toggle"
    payload_off: "toggle"
    state_on: 2
    state_off: 0
    icon: mdi:chart-bubble
  
  - platform: mqtt
    name: "Hot Tub Pump 2 (Seats)"
    state_topic: "homie/bwa/spa/pump2"
    availability:
    - topic: "homie/bwa/$state"
      payload_available: "ready"
      payload_not_available: "lost"
    command_topic: "homie/bwa/spa/pump2/set"
    payload_on: "toggle"
    payload_off: "toggle"
    state_on: 2
    state_off: 0
    icon: mdi:chart-bubble

  - platform: mqtt
    name: "Hot Tub Pump 3 (Feet)"
    state_topic: "homie/bwa/spa/pump3"
    availability:
    - topic: "homie/bwa/$state"
      payload_available: "ready"
      payload_not_available: "lost"
    command_topic: "homie/bwa/spa/pump3/set"
    payload_on: "toggle"
    payload_off: "toggle"
    state_on: 2
    state_off: 0
    icon: mdi:chart-bubble

  - platform: mqtt
    name: "Hot Tub Light"
    state_topic: "homie/bwa/spa/light1"
    availability:
    - topic: "homie/bwa/$state"
      payload_available: "ready"
      payload_not_available: "lost"
    command_topic: "homie/bwa/spa/light1/set"
    payload_on: "true"
    payload_off: "false"
    state_on: "true"
    state_off: "false"
    icon: mdi:car-parking-lights

Sensors

- platform: mqtt
  name: "Hot Tub Circulation Pump"
  state_topic: "homie/bwa/spa/circpump"
  availability:
   - topic: "homie/bwa/$state"
     payload_available: "ready"
     payload_not_available: "lost"
  icon: mdi:sync

- platform: mqtt
  name: "Hot Tub Priming"
  state_topic: "homie/bwa/spa/priming"
  availability:
   - topic: "homie/bwa/$state"
     payload_available: "ready"
     payload_not_available: "lost"

- platform: mqtt
  name: "Hot Tub Temperature Scale"
  state_topic: "homie/bwa/spa/temperaturescale"
  availability:
   - topic: "homie/bwa/$state"
     payload_available: "ready"
     payload_not_available: "lost"

- platform: mqtt
  name: "Hot Tub Heating"
  state_topic: "homie/bwa/spa/heating"
  availability:
   - topic: "homie/bwa/$state"
     payload_available: "ready"
     payload_not_available: "lost"
  icon: mdi:hot-tub

- platform: mqtt
  name: "Hot Tub Temperature Range"
  state_topic: "homie/bwa/spa/temperaturerange"
  availability:
   - topic: "homie/bwa/$state"
     payload_available: "ready"
     payload_not_available: "lost"
  icon: mdi:thermometer-lines

- platform: mqtt
  name: "Hot Tub Current Temperature"
  state_topic: "homie/bwa/spa/currenttemperature"
  unit_of_measurement: "°F"
  availability:
   - topic: "homie/bwa/$state"
     payload_available: "ready"
     payload_not_available: "lost"

- platform: mqtt
  name: "Hot Tub Filter 1 Cycle Running"
  state_topic: "homie/bwa/spa/filter1"
  availability:
   - topic: "homie/bwa/$state"
     payload_available: "ready"
     payload_not_available: "lost"
  icon: mdi:air-filter

- platform: mqtt
  name: "Hot Tub Filter 2 Cycle Running"
  state_topic: "homie/bwa/spa/filter2"
  availability:
   - topic: "homie/bwa/$state"
     payload_available: "ready"
     payload_not_available: "lost"
  icon: mdi:air-filter

Numbers

- platform: mqtt
  unique_id : hot_tub_set_temp
  name: "Hot Tub Set Temperature"
  state_topic: "homie/bwa/spa/settemperature"
  command_topic: "homie/bwa/spa/settemperature/set"
  min: 80
  max: 104
  availability:
  - topic: "homie/bwa/$state"
    payload_available: "ready"
    payload_not_available: "lost"
  icon: mdi:thermometer

Input Select

input_select:
  hottub_mode:
    name: Hot Tub Mode
    options:
      - ready
      - rest
      - ready_in_rest
  hottub_temperature_range:
    name: Hot Tub Temperature Range
    options:
      - high
      - low

Automations to support the selectors

- alias: "Update Spa Heating Mode Selector"
  trigger:
    platform: mqtt
    topic: "homie/bwa/spa/heatingmode"
   # entity_id: input_select.thermostat_mode
  action:
    service: input_select.select_option
    target:
      entity_id: input_select.hottub_mode
    data:
      option: "{{ trigger.payload }}"

- alias: "Set Hot Tub Heating Mode"
  trigger:
    platform: state
    entity_id: input_select.hottub_mode
  action:
    service: mqtt.publish
    data:
      topic: "homie/bwa/spa/heatingmode/set"
      payload: "{{ states('input_select.hottub_mode') }}"

- alias: "Update Hot Tub Temperature Range Selector"
  trigger:
    platform: mqtt
    topic: "homie/bwa/spa/temperaturerange"
   # entity_id: input_select.thermostat_mode
  action:
    service: input_select.select_option
    target:
      entity_id: input_select.hottub_temperature_range
    data:
      option: "{{ trigger.payload }}"

- alias: "Set Hot Tub Temperature Range"
  trigger:
    platform: state
    entity_id: input_select.hottub_temperature_range
  action:
    service: mqtt.publish
    data:
      topic: "homie/bwa/spa/temperaturerange/set"
      payload: "{{ states('input_select.hottub_temperature_range') }}"

Automations to heat the tub when I have excess solar and PG&E isn't charging an arm and a leg per kWH

- alias: "Set Hot Tub Temperature Ready"
  trigger:
    platform: time
    at: "11:00:00"
  condition:
    condition: state
    entity_id: group.family
    state: "home"
  action:
    service: mqtt.publish
    data:
      topic: "homie/bwa/spa/settemperature/set"
      payload: "99"

- alias: "Set Hot Tub Temperature Standby"
  trigger:
    platform: time
    at: "17:00:00"
  action:
    service: mqtt.publish
    data:
      topic: "homie/bwa/spa/settemperature/set"
      payload: "80"