Controlling Heat pumps / HVAC systems

[oliviers]

Hello to the Domoticz community,
I would like to share with you how I managed to control my heat pumps from Domoticz.
Heat pumps (splits) come with an IR remote to contol them. Some also come with an (expensive) optional WIFI module, but here's another solution to emulate the original IR remote.

The peculiarity of the IR commands used by heat pumps is that, each time you press any button on the remote, the whole desired settings are sent back to the device: On or Off, Heating or cooling, fan speed, vanes position, temperature, ... which results in rather long messages. A basic IR remote used to control a TV or a sound system is not able to learn ans send back such messages.

My solution relies "IrTrans" modules (Googelize that name to learn more). Those modules connect to your home network via Wifi or via Wired ethernet. They can learn long messages and repeat them when they receive an HTTP request via the network.

Thus the first step is to have the IrTans module learn the Heat pump IR codes. This is achieved with the supplied windows SW, by putting the module in "learning" mode and listen to the commands of the original remote.

One ends up up with a list of learned commands in the Irtrans module, such as:

Code: Select all

[COMMANDS]
  [poweron_16][T]0[D]2110001001101001101100100100000000000000000000100000100000000000000001100101111100110001000000000000000000000000000000000000000000000000000001100431100010011010011011001001000000000000000000001000001000000000000000011001011111001100010000000000000000000000000000000000000000000000000000011000
  [poweron_21_quiet][T]0[D]2110001001101001101100100100000000000000000000100000100001010000000001100101010100110001000000000000000000000000000000000000000000000000010110000431100010011010011011001001000000000000000000001000001000010100000000011001010101001100010000000000000000000000000000000000000000000000000101100000
  [poweron_21_medium][T]0[D]2110001001101001101100100100000000000000000000100000100001010000000001100010010100110001000000000000000000000000000000000000000000000000001010000431100010011010011011001001000000000000000000001000001000010100000000011000100101001100010000000000000000000000000000000000000000000000000010100000
  [poweron_21_high][T]0[D]2110001001101001101100100100000000000000000000100000100001010000000001100001010100110001000000000000000000000000000000000000000000000000000110000431100010011010011011001001000000000000000000001000001000010100000000011000010101001100010000000000000000000000000000000000000000000000000001100000
  [power_off][T]0[D]2110001001101001101100100100000000000000000000000000100001010000000001100001010100110001000000000000000000000000000000000000000000000000000110111431100010011010011011001001000000000000000000000000001000010100000000011000010101001100010000000000000000000000000000000000000000000000000001101110
  [poweron_21_med_vane][T]0[D]2110001001101001101100100100000000000000000000100000100001010000000001100010111100110001000000000000000000000000000000000000000000000000001001100431100010011010011011001001000000000000000000001000001000010100000000011000101111001100010000000000000000000000000000000000000000000000000010011000
  [poweron_21_high_vane][T]0[D]2110001001101001101100100100000000000000000000100000100001010000000001100001111100110001000000000000000000000000000000000000000000000000000101100431100010011010011011001001000000000000000000001000001000010100000000011000011111001100010000000000000000000000000000000000000000000000000001011000

Now install the IrTrans module in sight of the HVAC split you want to pilot, and send an HTTP request to the IrTrans module: It will emit the corresponding Ir code:
F. ex:

Code: Select all

http://192.168.0.18/send.htm?remote=pac_hitachi&command=poweron_21_medium

This can be done from any browser,a linux wget command, or from a Domoticz virtual switch.

I'm doing this for my HVAC systems. Cold or Warm, it's just a matter of "teaching" the corresponding Ir codes to the IrTans modules.

IrTans modules aren't cheap, however.... but they are cheaper than the WIFI modules sold by the HVAC vendors, and by using optional IR led repeaters, one module might be enough to control several HVACs. And you can also use the same module to pilot other Ir controlled devices such as an entertainment system or home cinema. It's just a matter of teaching it the right Ir codes.

Enjoy,
Oliviers

[chelsey12]

Without control system, the system will become unstable and HVAC would overheat or overcool. Thanks for sharing this with us its really great.

[Toni]

I have written an Arduino library for this purpose, here are some links:

https://github.com/ToniA/arduino-heatpumpir
https://www.openhardware.io/view/41/Hea ... controller
http://www.esp8266.nu/forum/viewtopic.p ... 8870#p8870

[SteveGranger]

Then install the control system so that everything will work properly and you will see no issue while accessing it. Contact local air conditioning companies to help you installing the best control system for your HVAC unit.

[DonaWigan]

But you can't control allergens to come in your home, but after having air duct cleaning you can prevent their entry.