Zehnder/Stork WHR Ventilation Unit

[adorobis]

Apparently there is an Issue that is describing exactly this aspect:
https://github.com/gieemek/ComfoAir_Bin ... d/issues/1
will give it a try.

[adorobis]

Sorry I can't write the scripts and code, I really don't know where to find this "SWITCH".. and I use domoticz, so if someone can convert this code for tolk to domoticz it will be great for me.

I know how to do it in Home Assistant, they have great integration with MQTT but no clue about DOMOTICZ...

[tice]

I have a Zehnder WHR920 Plus as a ventilation unit and I found this useful thread about a month ago. My primary goal was to control the ventilation unit based on the CO2 level.
My setup:
- Zehnder WHR920 Plus L
- 2 RFZ Sender transmitters
- 1 CC Ease Control Unit
- Domoticz
- 1 Domoticz integratable CO2 meter (AurAir).
- Sapiens script as described in the first message of this thread and found here on Github: https://github.com/AlbertHakvoort/Stork ... z-MQTT.git
- Raspberry PI Zero W hooked up to the serial port of the WHR920 via a USB to serial cable.

After making some changes to the original setup, my goal has been achieved! As a big thank you to Sapiens and the other folks on this thread, I decided to share my setup, hoping others benefit from this as well:

Problem: The script (whr930.py) effectively read some data, but the readings were odd and after some time the script errored in "division by zero" error. This thread contains some messages from people with similar experiences.

Analysis: The script assumed that it was the only "speaker" on the serial port, which is effectively so for anyone that does not have a CC Ease, but when a CC Ease is part of your setup, there is abundant communication between CC Ease and the WHR. The script that interprets the stream of data coming from the WHR has to make sure it filters out the communication between CC Ease and WHR! Serial communication can be thought of as:
1) script asks a question to WHR
2) WHR hopefully responds to question of step 1 while at the same time chatting constantly with CC Ease
3) script decodes messages and publishes MQTT messages (which are used for Domoticz)

Resolution: I changed the script so that step 3 is handled differently: The script now reads the first message from a queue and checks whether the message is the answer to the question of step 1 (this is a new check). If it is, business is as usual, ie publish MQTT messages, if it isn't, try the next message on the queue. Allow up to 9 consecutive messages to be scrutinized in this way. If after a total of 10 attempts no answer to the question was found, just give up and wait for the next cycle. I changed the default cycle time to 60 seconds (from 10 seconds).

Other changes: Another change is that the script now assumes two selectors to be present. The first selector is the existing one. The second selector is for display only purposes and makes sense in my particular setup where I control the desired fansetting based on the CO2 measured.

2020-03-03 13_55_37-Domoticz.png (37.28 KiB) Viewed 4070 times

.

If you don't control the fan in this way you could set the IDX of the sliders to be the same. If you do: I included my lua script (dzventz) as an attachment:

control_co2.lua.txt

(1.03 KiB) Downloaded 101 times

I also removed the part in the script that reported on FanlevelSpeed and RPM, because the readings I received from them where strange and I assessed that I would have to change the program in order for the readings to be logical but since those readings did not interest me in the first place I decided on removing that part.

The default IDX's at the top of the script reflect my own setup, but this is of no consequence because you were going to have to change that anyway.

You can find my modified version of Sapiens' script here: https://gitlab.com/matthijs_rademakers/ ... z-MQTT.git

[jboesh]

.

[legan]

Hi,

I'm trying to setup the Zenhnder ComfoAir Q450 with a NodeMCU and MAX3232, but I cannot get the thing to work. I know the NodeMCU and MAX3232 are working correctly, as I tested on other devices with a RS232 connection.

What I did so far:

- Connected the the NodeMCU as follows to the MAX3232 converter
- NodeMCU 3v to MAX3232 Vcc
- NodeMCU Rx to MAX3232 Tx
- NodeMCU Tx to MAX3232 Rx
- NodeMCU Gnd to MAX3232 Gnd

- Connected MAX3232 DB9 to Zehnder ComfoAir Q450
- MAX3232 DB9 pin 2 to Zehnder white labeled connector
- MAX3232 DB9 pin 3 to Zehnder yellow labeled connector
- MAX3232 DB9 pin 5 to Zehnder black labeled connector

The NodeMCU is flashed with esplink and when entering commands in the console, I don't see any response coming from the zender.
I have already swapped pin 2 and 3 (tx/rx).

Now, what can I do to test if I have a working connection?
In the esplink console I have already tried sending 'x07\xF0\x00\x0F\x00\xBC\x07\x0F' to get the temperature, but I don't get a response.

I would like to see that I can obtain/set values even before hooking up with domoticz.

Any help would be appreciated.

[rrozema]

Hi,
is there a way to control/connect the Whr 930 wireless in Domoticz? i cant wire the Whr with a converter, because it's placed in the attic unfortunately (and the Raspberry in the fuse box)

Thanks

Theoretically ser2net should be able to be of service. You would need an esp-32 module to make the serial connection into a network connection over wifi, that then can be connected to by your domoticz via the network. I am trying to this too, but I have no experience with multiple components of this solution. So also for me any suggestions are welcome.

[rrozema]

I could be that you have the same issue that I have: slightly different communication protocol. Did you try the official "Maintenance software" from Stork / Zehnder. You can download it from this thread:
https://www.promixis.com/forums/showthr ... R950/page3

If that works then jou know that your cables are OK and that the communication protocol is the issue.

Let me know what your findings are.

I've been trying to get my WHR 930 basic to talk to my raspberry PI for at least the 5th time now. I've tried 2 different usb-serial converters but I get no valid values from the serial port at all. I'm connecting to the RJ45 connector at 9600 N, 8, 1 and have tried many other speeds as well. I've tried switching rx and tx around. All I get is the tx light flashing when I send from the raspberry (or my pc), I never get a flashing light on the rx of my serial-usb.

Does anybody please still have that maintenance software (the forum link @ proximis.com doesn't work any more) so I can at least verify my wiring is correct? Any download link, direct message or even the exact file name(s) to look for would be greatly appreciated.

[rrozema]

I regsitered as an installer at zehnder's site and downloaded the software I could find there. I do see activity now on the serial-usb converter, both rx and tx, but the software says "No MX found". I think this tool is not for my WHR 930. Another tool says no/broken connection, but that's for a ComfoAir XL, which also doesn't sound right for a WHR 930 basic. I can't find any other softwares that bettermatch my unit.

[mogwai]

I regsitered as an installer at zehnder's site and downloaded the software I could find there. I do see activity now on the serial-usb converter, both rx and tx, but the software says "No MX found". I think this tool is not for my WHR 930. Another tool says no/broken connection, but that's for a ComfoAir XL, which also doesn't sound right for a WHR 930 basic. I can't find any other softwares that bettermatch my unit.

You can still find the SW here: https://www.roelbroersma.nl/media/downl ... pV2.53.zip

Good luck

[rrozema]

You can still find the SW here: https://www.roelbroersma.nl/media/downl ... pV2.53.zip

Good luck

Thank you so much. Sadly it still doesn't connect. But at least now I know where to look for the problem!

[hesselb]

I have a Zehnder WHR920 Plus as a ventilation unit and I found this useful thread about a month ago. My primary goal was to control the ventilation unit based on the CO2 level.



You can find my modified version of Sapiens' script here: https://gitlab.com/matthijs_rademakers/ ... z-MQTT.git

thanks works fine

Hessel

[qualityair]

Great and interesting solution.

Do you know if it can works for a comfoair 160?

Comfoair 160 wiring schema: http://imgur.com/a/xUM61

I have the same question, has anyone tried with comfoair 160 luxe?

[iamhaller]

-

[PiotrekB]

Hellow
Is there anybody who can/know how to change the code to read status of bypass.

exemple change the line to read status FAN RPM or similar to read / control bypass ?

[rrozema]

I have spent another sunday on this and I think I have to admit defeat: my WHR930 won't talk to me. I don't know what is wrong, but I've tried everything I can thik of and read here in this thread and it never responds. I have the official maintenance software installed in my windows 7 machine (both v2.53 downloaded from mogwai's link and 2.61 from the zehnder site), when I press 'Connect' the program flashes '...Search MX' for some time and on my FTDI232RL the rx-led (i think) flashes periodically until the program says 'No MX found'. I have switched lines 2 and 3 over as was suggested, but that made no difference either. I have tried several different cables, multiple usb-serial converters of different types and makes and nothing works. I may have somewhere down the line fried the serial port in my whr, i don't know and don't know what else to try. I would love to capture all the data and have my whr do tricks for me, but it's not going to happen sadly...

I anyone still has a suggestion what else to try or test I would be thankful, but I think it's over and out for me.

the main board for my whr930 basic

whr930 basic.jpeg (133.48 KiB) Viewed 3376 times

ftdi232 usb to rs232 converter

ftdi232rl.jpeg (75.81 KiB) Viewed 3376 times

[wichers]

I have spent another sunday on this and I think I have to admit defeat: my WHR930 won't talk to me. I don't know what is wrong, but I've tried everything I can thik of and read here in this thread and it never responds.

I have the same problem (WHR 950 II) with the exact same board layout as yours. I thought I had blown my port as well, so I replaced the PIC18F6622 and reflashed it with a PicKit2. Turns out it almost impossible for a pic18f to lose functioning ports and still have a working cpu.

As I've already dumped the firmware (I have version 1.4) https://pastebin.com/gy97ntD0 I thought I would do some reversing to see if there is actual uart code implemented. Good news there is, I have also verified that the baudrate is set to 9600. To be continued..

[wichers]

Ok, I finally got it working. I actually did break the RS232 logic conversion part of my WHR-950 Basic, I fixed this by replacing both the BC847B transistors. Now I can finish my esphome comfoair plugin.

@rrozema I noticed you're using the FT232RL chipset, this is for a TTL level device (0-5V), you really need RS232 (between +12V and -12V). If you don't want to buy a RS232 to USB dongle you could put a MAX3232 board between the FT232RL and the WHR.

[wichers]

I have a working esphome comfoair plugin now. My esp is powered by the WHR-950 and is natively communicating with home assistant. Esphome can also talk to an mqtt endpoint, so this should work with domoticz as well..

Note: I destroyed the transistors on the WHR mainboard by using an RJ45 female connector with built-in ethernet transformers. I was not aware that they existed within the connector..

[rrozema]

Ok, I finally got it working. I actually did break the RS232 logic conversion part of my WHR-950 Basic, I fixed this by replacing both the BC847B transistors. Now I can finish my esphome comfoair plugin.

@rrozema I noticed you're using the FT232RL chipset, this is for a TTL level device (0-5V), you really need RS232 (between +12V and -12V). If you don't want to buy a RS232 to USB dongle you could put a MAX3232 board between the FT232RL and the WHR.

Congratulations and thank you very much for the information. When I've got time, I will have another look at my whr930 basic's main board. I actually already have 3 different types of converters and for some of them I even have duplicates, all purchased in my search for a working one . I will have a proper look at these too, then reconsider which to apply based on your information.

[rrozema]

Anyone knows if the cable used to program cisco routers can be used? For example: https://nl.aliexpress.com/item/4001291550829.html

EDIT: I found the answer myself: the pins used for the cisco console cable on the rj45 connector are not the 2,3 and 8 used for our whr-units. So, the answer is: NO, it can not be used, (https://nl.aliexpress.com/item/32825439252.html)