Basic HVAC/Ventilation system support

[Sidiox]

This merge request adds basic support for ventilation systems.
Adds reading of the temperature sensors, some diagnostic info and fan control.

OpenThermIDs based on various spec sheets: 'OpenTherm Technical Specifications v2.3b' and 'OpenTherm-Function-Matrix-v1_0.xls'

Tested (and currently in use) for a Brink HRV.

[lmadean]

I also have a Brink HRV and would like to have this as well. Please merge the pull request.

[Sidiox]

I also have a Brink HRV and would like to have this as well. Please merge the pull request.

Have a look at my usage of my fork of the library if you have a Brink HRV (I have some more articles on how to hook up the hardware if you're interested): my article.

[crazypaddo]

Sidiox i have a brink wtw to are you willing to share your project file arduino ide ore vscode.
I am struggling to put all the software parts together but failed. I would like to integrate the system with the heatpump i installed to get the fans in sync.

[webstar-nl]

Sidiox i have a brink wtw to are you willing to share your project file arduino ide ore vscode. I am struggling to put all the software parts together but failed. I would like to integrate the system with the heatpump i installed to get the fans in sync.

Hi, I am experimenting as well with this Brink WTW and already got it running: reading and writing values. Great!

[crazypaddo]

Hello, i failed to get any data out off the wtw. Because i dont know how to use the opentherm example. Are you willing to shaire a example arduino ide or vscode to use with the brink renovent? Marco van oort Op 16 nov. 2021 om 20:31 heeft webstar-nl ***@***.***> het volgende geschreven:  Sidiox i have a brink wtw to are you willing to share your project file arduino ide ore vscode. I am struggling to put all the software parts together but failed. I would like to integrate the system with the heatpump i installed to get the fans in sync. Hi, I am experimenting as well with this Brink WTW and already got it running: reading and writing values. Great! — You are receiving this because you commented. Reply to this email directly, view it on GitHub<#36 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/AOGCO4KNJTCNDPOIK3TWTQDUMKWRDANCNFSM47AJQWXA>. Triage notifications on the go with GitHub Mobile for iOS<https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android<https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub>.

[Sidiox]

I can share my code, I'll try to get an example blog/github in a couple of days! It does presume knowledge of MQTT and Home-assistant how ever

[crazypaddo]

Hello sir, that would be very nice off you. I use mqtt and domoticz not home assistant but that should not be a problem i think. I also know a bit off the opentherm protocol, but i have had a lot off bad luck last weeks, so my mind isnt that clear. Thank you for your time and effort’s. Regards marco van oort Op 16 nov. 2021 om 21:29 heeft C. (Sidiox) ***@***.***> het volgende geschreven:  I can share my code, I'll try to get an example blog/github in a couple of days! It does presume knowledge of MQTT and Home-assistant how ever — You are receiving this because you commented. Reply to this email directly, view it on GitHub<#36 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/AOGCO4IU6BQAD4O6L7CDJH3UMK5KNANCNFSM47AJQWXA>. Triage notifications on the go with GitHub Mobile for iOS<https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android<https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub>.

[webstar-nl]

I will share my project as well, probably tomorrow. I use ESP32, programming over OTA and BLYNK for convenient interface. The nice thing of this opentherm protocol: as soon as you write 0 as setpoint Ventilation, device just stops.
Regards, Mark Wester

[crazypaddo]

Hi mark and sidiox Thank you. There are still people willing to help other people with out asking for money. You made my day a little better today. Thanks for your time and efforts. Regards marco van oort I will share my project as well, probably tomorrow. I use ESP32, programming over OTA and BLYNK for convenient interface. The nice thing of this opentherm protocol: as soon as you write 0 as setpoint Ventilation, device just stops. Regards, Mark Wester — You are receiving this because you commented. Reply to this email directly, view it on GitHub<#36 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/AOGCO4JH237NMAP5LMQCWH3UMLIFHANCNFSM47AJQWXA>. Triage notifications on the go with GitHub Mobile for iOS<https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android<https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub>.

[webstar-nl]

This is my Arduino project. It is 'as-is' see feel free to use it.
Just copied modified OpenTherm.CPP + OpenTherm.H in same directory as project.
Components:
ESP32 WROOM
ESP8266 Thermostat Shield from diyless.com
5 wires connected: +5 / GND / 21 / 22 / 18

#include "OpenTherm.h" //local > in same directory as INO
// ESP32 Dev Module
// 16/11/2021 ...
// OTA + BLYNK + OpenTherm
#define BLYNK_PRINT Serial
#define VERSION 02 // Version in BLYNK
#include <Blynk.h> //
#include <BlynkSimpleEsp32.h>
#include <WiFi.h>
#include <ESPmDNS.h>
#include <WiFiUdp.h>
#include <ArduinoOTA.h>
#include <Arduino.h>
#include <OneWire.h>
#include <DallasTemperature.h>

char auth[] = "xxxxxxxxxxxxxxxx";// BLYNK ESP32 11/2021
const char* ssid = "xxxxxxxxxxxxx";
const char* password = "xxxxxxxxxxxx";
int counter;
BlynkTimer timer;
WidgetTerminal terminal(V0); //Text
// Use Virtual pin 0 for current room temperature display
unsigned int WTW_SetVentilation; //V2
// Opentherm:
const int inPin = 21; //for Arduino, 4 for ESP8266 (D2), 21 for ESP32
const int outPin = 22; //for Arduino, 5 for ESP8266 (D1), 22 for ESP32
OpenTherm ot(inPin, outPin); // true = slave

//Temperature sensor pin
const int ROOM_TEMP_PIN = 18; //14 for ESP8266 (D5), 18 for ESP32

OneWire oneWire(ROOM_TEMP_PIN);
DallasTemperature sensors(&oneWire);
//////////////////////////////////////////////////////////////////////////
float getTemp() { return sensors.getTempCByIndex(0); }
void ICACHE_RAM_ATTR handleInterrupt() { ot.handleInterrupt(); }

BLYNK_CONNECTED(){ // Sync
Blynk.syncVirtual(V2); // Setpoint Ventilatoin %
Blynk.virtualWrite(V50, VERSION);
}

BLYNK_WRITE(V2) { // Setpoint WTW
WTW_SetVentilation = param.asInt();
}

void setup() {
Serial.begin(115200);
terminal.println("Booting");
WiFi.mode(WIFI_STA);
Blynk.begin(auth, ssid, password);
delay(100);
while (WiFi.waitForConnectResult() != WL_CONNECTED) {
Serial.println("Connection Failed! Rebooting...");
delay(5000);
ESP.restart();
}
ArduinoOTA.setHostname("Esp32");
ArduinoOTA.onStart( {
String type;
if (ArduinoOTA.getCommand() == U_FLASH)
type = "sketch";
else // U_SPIFFS
type = "filesystem";
Serial.println("Start updating " + type);
});
ArduinoOTA.onEnd( { Serial.println("\nEnd"); });
ArduinoOTA.onProgress([](unsigned int progress, unsigned int total) {
terminal.printf("Progress: %u%%\r", (progress / (total / 100)));
});
ArduinoOTA.onError([](ota_error_t error) {
terminal.printf("Error[%u]: ", error);
if (error == OTA_AUTH_ERROR) terminal.println("Auth Failed");
else if (error == OTA_BEGIN_ERROR) terminal.println("Begin Failed");
else if (error == OTA_CONNECT_ERROR) terminal.println("Connect Failed");
else if (error == OTA_RECEIVE_ERROR) terminal.println("Receive Failed");
else if (error == OTA_END_ERROR) terminal.println("End Failed");
});
ArduinoOTA.begin();
terminal.println("Ready");
terminal.print("IP address: ");
terminal.println(WiFi.localIP());
//
terminal.clear();
terminal.println(F("Blynk v" BLYNK_VERSION ": Device started"));
terminal.flush();
timer.setInterval(5000L, DataOpentherm); // 1.0 s
ot.begin(handleInterrupt);
// ot.begin(handleInterrupt, processRequest);
//Init DS18B20 sensor
sensors.begin();
sensors.requestTemperatures();
sensors.setWaitForConversion(false); //switch to async mode
}

void loop() {
Blynk.run();
ArduinoOTA.handle();
timer.run();
ot.process();
} // loop
//-----------------------------//

void DataOpentherm() {
//Set/Get WTW Status
ot.setVentilation(WTW_SetVentilation); // Setpoint! V2 from BLYNK

unsigned int WTW_gVent = ot.getVentilation();
bool WTW_gVMode = ot.getVentilationMode();
float WTW_gVSIT = ot.getVentSupplyInTemperature();
float WTW_gVSOT = ot.getVentSupplyOutTemperature();
float WTW_gVEIT = ot.getVentExhaustInTemperature();
float WTW_gVEOT = ot.getVentExhaustOutTemperature();
terminal.println("WTW Ventilation%: " + String(WTW_gVent));
terminal.println("WTW VentilationMode: " + String(WTW_gVMode));
terminal.println("WTW VentSupplyInTemperature: " + String(WTW_gVSIT));
terminal.println("WTW VentSupplyInTemperature: " + String(WTW_gVSOT));
terminal.println("WTW VentSupplyInTemperature: " + String(WTW_gVEIT));
terminal.println("WTW VentSupplyInTemperature: " + String(WTW_gVEOT));
Blynk.virtualWrite(V3, WTW_gVent);
Blynk.virtualWrite(V4, WTW_gVMode);
Blynk.virtualWrite(V5, WTW_gVSIT);
Blynk.virtualWrite(V6, WTW_gVSOT);
Blynk.virtualWrite(V7, WTW_gVEIT);
Blynk.virtualWrite(V8, WTW_gVEOT);

float temperature = sensors.getTempCByIndex(0);
terminal.println("OT Room temperature is " + String(temperature) + " C");
terminal.println("-------------------------------");
Blynk.virtualWrite(V1, temperature);
terminal.flush();
}
/*
VentStatus = 70, // flag8 / flag8 Master and Slave Status flags specific to Vent systems
VentNomVentSet, // _ / u8 Set the relative ventilation 0-100%
VentFault, // flag8 / flag8 Application specific fault flags
VentOEMFault, // flag8 / flag8 Oem specific fault flags
VentSlaveVentConfig = 74, // Slave Configuration Flags / Slave MemberID Code
VentNomVent = 77, // _ / u8 Read the relative ventilation 0-100%
VentRelHumid, // _ / u8 Read the relative humidity 0-100%
VentCO2level, // u16 CO2 level in PPM (0-2000)
VentTsupplyin, // f8.8 Supply Outlet temperature
VentTsupplyout, // f8.8 Supply Outlet temperature
VentTexhaustin,// f8.8 Exhaust Inlet temperature
VentTexhaustout, // f8.8 Exhaust Outlet temperature
VentRPMexhaust, // u16 Actual RPM for inlet fan
VentRPMsupply, // u16 Actual RPM for supply fan
VentNomRelVent = 87, // _ / u8 Get the current relative ventilation
*/

[Sidiox]

Here is a repo that shows how I use my fork of the library with home-assistant: https://github.com/Sidiox/hrv-control

See my blog for more details on the hardware and such.

[crazypaddo]

Hi sir, Thank you for the example. I will study it and try to see how you used it. Again thank you. Mvg marco van oort

[crazypaddo]

Hello sidiox, Could you please tell me the brink model you have and got data rcieved? I have a brink renovent hr medium 2009 and a large unit 2011. The esp does send data to mqtt and i can set the speed true mqtt. But i dont get temperatures bypass data supplyrpm exhaust rpm co2 and humidity. Now i noticed the co2 humid and rpms aren't included in the opentherm files. So i tryed to add them. It compiles and runs, but i suspect interrupts arent working ore the ota part i added interfears with the interrupts. I have a otgw to and that does recieve the bypass status. So i am a little confused what to try next. Maybee my brink wtw is to old. Regards marco van oort

[Sidiox]

My Brink HRV is I think a medium from that same era.
Keep in mind that not all sensors are available in those units.
OpenTherm has 4 temperature ids, but I can only read 2. (There are only 2 physical temperature sensors in the unit and no CO2 sensors either and no humidity sensors either).

I'd try running an OpenTherm ID scan. I've added my scanning code to my repo: Scanner
I explain some of my process here: Blog

I got the following IDs:

70
72
74
75
77
80
81
82
83
86
88
89

I did find that Brink doesn't seem to quite follow the spec, but these IDs are plenty to control the HRV.

[webstar-nl]

I also don't get all data, most likely because not all sensors are implemented in standard equipment. But control speed, read supply inlet temperature and exhaust inlet temperature for me is enough.

[crazypaddo]

Hello guys, thank you for the reply. I realize i need to give some more info. I did read the opentherm documents the brink manual and installation manual. So i know there are normally only 2 temp sensors mounted in the wtw and no co2 and humid. I understand the wtw ids needed to be added to the opentherm lib. Thanks for that. But i wasn’t clear enough, I have a option print thats is used with brink wtw to provide co2 and humidity. And i have 4 temp sensors mounted in my wtw (bought a broken wtw for the parts). I suspected a hardware failure on my otgw. I swapped the otgw, for my reserve otgw. After testing coms with wtw and otgw. I was able to get some data out off the brink. So indeed something broke on my otgw. With working otgw without pic mounted and new nodemcu, with your ino file i got data. 2 temperatures and rpm. I recieve the data in mqtt and node red. After that i replaced the file with my ino file with co2 humid exhuastrpm supplyrpm and 4 temperature sensors. That also worked but no data for co2. And rpm’s. I think it is because it uses u16 for co2 and exhaust rpm and supply rpm ids to get the data. I see in opentherm files a part for the float and u8 data. But not for u16 and dont seem to understand how to combine the msb and lsb to one value in opentherm file. Butinalso noticed the exhaustrpm and supplyrpm ids are not noted in the list the scanner provides. Thanks again for your time and efforts Marco van oort

[Sidiox]

If the scanner doesn't return the IDs then the HRV either doesn't support them or doesn't have them, or its encoded in another id. My scanner just does a raw read, so the HRV should always respond.

The scanner should also provide the raw data so it should be semi doable to reverse engineer most of the unknowns if I didn't implement them if you use the various specs floating around. I have an excel sheet with all the HRV IDs and their official designation, but Brink doesn't quite follow that spec sheet.

I remember I couldn't get the RPM readings. You can look at the raw scanner 0 and 1s, but I think I had some problem with that (either it didn't respond or didn't make sense).

[raf1000]

Hello, I have managed to access all (or almost all) data available at Brink Renovent HR including adjustable parameters (TSP). You can find details here: (https://github.com/raf1000/brink_openhab)
The Arduno directory includes codes you can leverage in your project.
In case of questions please use the link as above.

PS. Based on my experience the otgw does not process all brink data :-( as it was designed for heating. the solution deecribed in the link above provides all avaiable data.