node-red-contrib-komfovent v0.4.0-rc.1

Node-red-contrib-komfovent

This package contains nodes to work with Komfovent ventilation units, mainly with the C6 controller with built-in webserver. The node supports the (way too basic) web auth for this unit and uses the ajax calls to integrate. Currently support for changing modes and fetching status/metric/sensor data.

This package is by no means associated with or supported by the actual vendor of the ventilation units, but should be perfectly safe to use, as it only replicates the exact actions of the web based controller.

Latest changes

See changelog, but please note package now contains a getter node, screen scraping komfovent for detailed metrics. This adds dependencies.

To install

npm install node-red-contrib-komfovent

or clone/download and use/modify it yourself. After download, switch to your .node-red folder and

npm link <path to package>

You can then edit and work on it, all changes available in node-red with just a restart (node-red-stop & node-red-start)

Updating

NB! Breaking changes from 0.3 to 0.4 due to full refactor, new Node-red versions etc.

Nodes

Config

This node basically contains your credentials and the config values the other nodes will use for sending commands. the values Komfovent accepts for the different modes are stored here, as of now not available from config.

KomfoventNodeSet (set mode)

This is the first action node, that will let you activate the different modes of the unit.

Auto - The unit will either follow the chosen program (workweek etc) or manage speed based on sensors if installed (humidity, temp)
Away - Usually a low intensity mode, based on your settings
Home - the setting for operating normally when at home. Should have been calibrated by your installation vendor
Intensive - for hot days or extra people in the house, fans at higher speeds
Boost - for when you really need to exchange that air

Please note that in the C6 webcontroller, the Auto and Eco modes are toggle switches. If you call it once, auto mode is activated. Twice, and it falls back to last known standard mode (away, normal etc). If nodes are used for automating based on events from other system, you should handle this state with other nodes.

Input and results

The node takes strings as input, the name of the wanted operating mode or blank ('') to fetch current mode, without changing it.

msg.payload = 'intensive';

Return values are either the mode if success, or errorobject if error. The error returned is logged.

{ error: true, result: 'wrong password', unit: 192.168.x.x }
{ error: false, result: 'auto', unit: 192.168.x.x }
{ error: true, result: 'Unsupported mode', unit: 192.168.x.x } 

Note that the returned mode is what was passed to the node, not an actual return from the C6 controller confirming mode. Fetch updated mode to verify this. Result can also be stringified error object from Request.post, on errors not handled specifically by this node.

KomfoventNodeGet (get data)

This is the node for fetching status and metrics available from the web page of the controller.

Input and results

The node takes a string as input, id of the datafield wanted. You can get a list of the most common below or use dev tools or view source of komfovent to find the IDs you want. However, please note that the scraper being used, Cheerios, does not support iframes. So IDs found here will not be extracted as of now. Food for future releases. This node however as specific support to scrape the det.html page instead if id names contains underscore.

msg.payload = 'ai0' // would return string value of supply temp, in the json object shown below

Please note that as of now, return values includes the type, the unit the value is set in, as defined in the web page. And the same capitalization.

Errors are printed to the log, and simple error objects returned. Normal return objects below { error: false, result: '16.6 C', unit: 192.168.x.x } { error: false, result: 'BOOST', unit: 192.168.x.x } { error: false, result: '40 %', unit: 192.168.x.x }

Field names

These are case sensitive

Temperature and environment

• ai0 is supply temperature
• ai1 is extract temperature
• ai2 is outdoor temperature
• rh is relative humidity in percentage
• v_s1 is sensor 1 humidity if present % (if sensor installed)
• v_s2 is sensor 2 humidity if present % (if sensor installed)
• v_ph1 is panels humidity level % (if panel provides this)

Heating

• ec2 is heat recovery measurement
• ec4 is current heating power in watts
• ec1 is current heat exchanger effecieny in %
• ec7d is kWh spent on heating for current day. ec7m is for month and ec7t total
• v_eh is heater operating level

System metrics and status

• fcg is filter clogging level %
• ec3 is current power consumption
• ec8d is recovered energy in kWh current day. ec8m for month, ec8t total
• ec6d is consumed energy in kWh for the day. ec6m for month and ec6t for total
• v_ad is air dampers %
• v_es is energy saving level
• omo is current fan mode

Pressure

• saf is suppy flow in percentage
• eaf is extract airflow in percentage

Future

Add support for more modes also with timers(fireplace, kitchen ventilation etc) Surfarcing the actual commands sent in the config node might also be relevant in the future, making them available for change by configuration. For scraping, adding support to fetch which modes and controls are activated, other than actual fanspeed. Maybe adding support for specifically handling the modes implemented as toggle switches (auto, eco) and remove the toggle issue of the controller. But this has multiple state/quality/troubleshooting/logic implications and would require scraping actual data from the controller first, might end up a separate node to handle that when applicable in users flows.

Handling toggle switches

Auto and eco mode is toggling the modes when called. If you call it once, auto mode is activated. Twice, and it falls back to last known standard mode (away, normal etc). This can be handled quite easily in node-red. Make a global context variable tracking if you have called it or not and use a switch or function node to implement your logic. My function node for this in an earlier implementation:

if (global.get("autoIsSet") && msg.payload =="285=2") {
	msg = null;
	// do not call twice, value is toggling the controller mode
	node.status({text:"Already set intense - stop"});
}
else if (!global.get("autoIsSet") && msg.payload == "285=2") {
	global.set("autoIsSet",true);
	//call and flag not to call it twice
	node.status({text:"Setting intense - flag"});
}
else {
	global.set("autoIsSet", false);
	node.status({text:"Intense flag false"});
}
return msg;

Security

The basic and not very trustworthy security of the unit means that you should take care when integrating witt and exposing it. Never put it directly online, integrate locally or secure your communications and terminate it as close to the unit as possible. Please not that the units c6 controller does not support SSL/TLS. Do make sure that you do not reuse a password from your other services or IoT devices etc.

Komfovent class

Foundational module for all nodes, Komfoventclass. Contains functions for get/set modes, get data.

• getMode(ip)
• setMode(mode, ip) where mode is {name: 'auto|away|etc, code:'285=2'}
• getId(id, ip) where id is the name of datafield to fetch
• logon(username,password,ip)

All functions are stateless and does new requests to the unit each time called. Public functions listed below validates input and returns json objects as described above, for results and errors. Private functions does not, they throw and do not validate input.

Troubleshooting

Due to the annoying nature of ventilation systems and their lacking capabilities in digitalization, there is a lot more debug output from this node than I would usually add. To use it, run node-red -debug

Most errors will be surfaced in the returned json structure and the most common ones is handled specifically (wrong password, host not found).

The node is tested against the C6 controller running 1.3.14.14 firmware, being a bit inconsistent in logon and having issues setting mode. Main part of the work has been done with the newer 1.3.17.20 firmware. See the komfovent.com webpage for end users and downloads to find the newest firmware and instructions on how to update. (Download the bin file, turn of the fan, go to http://yourunit/g1.html, upload bin file and wait. Mind that if you are far behind, there could be intermediate upgrades to go through first.)

The units built in webserver handles auth by receiving the body of 1=username&2=password. The system will return HTTP 200 even when auth fails, just hihglighting "incorrect password" in the page sent back. Mode is set by posting to the ajax.xml file, with a body of for instance 3=1, 3=2 etc. Note that Automode is called by 285=2, but this is a toggle switch. Calling it twice will have the system go back to the last mode activated. In automode, the system will alter fanspeed based on either sensors or the weekly plan you have defined.

Please note that timeouts can be long for wrong or not reachable hosts, as this would be defined by the OS TCP/IP timeout settings.

Also, look at reverse.md file for more details and design considerations.

Networking

The C6 controller only supports physical ethernet connection, the rj45 to be found inside the unit, with specific channels to lead the cable through. A wireless bridge can then be attached and get the unit on your wifi. From experience, these ventilation units are often placed in non-hospitable areas of buildings, that can become very damp, warm, cold etc. Make sure your electricity and wifi bridge is up the the job.

Another trick is to connect the bridge to power by using for instance a fibaro plug. Then its quite easy to reset the device in case of issues, avoding having to crawl into the attic or wherever your ventilation unit is placed.

Komfovent C6 also seems to throw Connection reset once in a while, at least when I do dev and log on often. Recieve ECONRESET or EPIPE CLOSED.

Legal Disclaimer

This software is not affiliated with Komfovent and the developers take no legal responsibility for the functionality or security of your ventilation systems and devices. Neither does any of the contributers/dependecies to this package. Treat your credentials with the uthermost care and do not change settings you do not understand on the ventilation unit. Ethernet connection should only be set up like described in the manual.