HeatPump

Arduino library to control Mitsubishi Heat Pumps via connector CN105.

Quick start

Controlling the heat pump

HeatPump hp;
hp.connect(&Serial);

heatpumpSettings settings = {
    "ON",  /* ON/OFF */
    "FAN", /* HEAT/COOL/FAN/DRY/AUTO */
    26,    /* Between 16 and 31 */
    "4",   /* Fan speed: 1-4, AUTO, or QUIET */
    "3",   /* Air direction (vertical): 1-5, SWING, or AUTO */
    "|"    /* Air direction (horizontal): <<, <, |, >, >>, <>, or SWING */
}; 

hp.setSettings(settings);
// OR individual settings
// hp.setModeSetting("COOL");

hp.update();

See heatPump_test.ino

Getting updates from the heat pump

void setup() {
  HeatPump hp;
  hp.connect(&Serial);
}

void loop() {
  hp.sync();

  /* get settings from heatpump, including room temperature in settings.roomTemperature */
  heatpumpSettings settings = hp.getSettings();
}

Contents

• sources
• sample usage code
• Demo circuit using ESP-01

Installation

• PULL or download zip.
• Move contents into Arduino library directory
• Restart IDE, samples should be avaliable
• NOTE: Requires arduino json 6, older commits before 20190505 support json 5.
• If you find this all a little confusing, check out this write up blog/install by Chris Davis
  • https://chrdavis.github.io/hacking-a-mitsubishi-heat-pump-Part-1/
  • https://chrdavis.github.io/hacking-a-mitsubishi-heat-pump-Part-2/
    • Note: some people report problems with Wemos D1 due to usb serial pulling RX high when usb idle! Fix is to cut a trace, so maybe use an alternative, if following the above blog links.

Notes

• Tested with ESP8266
• Tested with Arduino Micro Pro / Arduino Nano
• Tested with Mitsubishi HeatPump MSZ-FH/GE(wall units) and SEZ-KD (ducted units) complete list

Demo Circuit

Parts

Parts required to make a CN105 female connector

• PAP-05V-S CONN HOUSING PA 5POS 2MM WHITE
  • Digi-Key Part Number 455-1489-ND
  • https://www.digikey.com/product-detail/en/jst-sales-america-inc/PAP-05V-S/455-1489-ND/759977
• SPHD-002T-P0.5 CONN TERM PHD CRIMP 24-28AWG TIN
  • Digi-Key Part Number 455-1313-1-ND
  • https://www.digikey.com/product-detail/en/jst-sales-america-inc/SPHD-002T-P0.5/455-1313-1-ND/608809
• JUMPER SPHD-001T-P0.5 X2 12" (pre-crimped alternative to 455-1313-1-ND connectors)
  • Digi-Key Part Number 455-3086-ND
  • https://www.digikey.co.uk/product-detail/en/jst-sales-america-inc/APAPA22K305/455-3086-ND/6009462

Other part suggestions

• Premade pigtails
  • http://www.usastore.revolectrix.com/Products_2/Cellpro-4s-Charge-Adapters_2/Cellpro-JST-PA-Battery-Pigtail-10-5-Position
• ESP-01 module (4pk)
  • https://www.amazon.com/gp/product/B01EA3UJJ4/
• Cheap 5V to 3.3V regulator (10pk), for those that don't want to make one
  • https://www.amazon.com/gp/product/B00XAGSHY2/
• ESP-01 breakout with prewired level shifters and regulator
  • https://www.amazon.com/gp/product/B01M09B43H/

Special thanks

... to Hadley in New Zealand. His blog post, describing baud rate and details of cn105, Raspberry Pi Python code:

https://nicegear.co.nz/blog/hacking-a-mitsubishi-heat-pump-air-conditioner/

License

Licensed under the GNU Lesser General Public License. https://www.gnu.org/licenses/lgpl.html