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Thermostat disconnected error
Posted: Fri May 29, 2015 4:57 pm
by rkoebrugge
I recently bought a OTWG at Kiwi Electronics, which should be tested and working properly.
After connecting the CV (Boiler) and thermostat, the logging receives messages from the CV about water temperature and everything else. Unfortunatly the OTMonitor software is not showing any information about the Thermostat and also displays a message saying that the thermostat is not connected. With the diagnose firmware loaded I tried some tests, but they do not give any information which tells me what the issue is.
Here is the export of some tests. Test 2 and 3 displays nothing. Voltage is both 0 volt on boiler and thermostat.
Could anyone please help and give me feedback about what to do? I tried playing around with reference voltages, but that does not give me the solution. On the thermostat the display keeps telling me there is an OT error and the logging of OTMonitor is not recognising/connecting to the thermostat.
Thank you in advance

Re: Thermostat disconnected error
Posted: Fri May 29, 2015 8:40 pm
by hvxl
The thermostat disconnected indication is not technically an error. However, the indication should obviously not appear when a thermostat is connected.
Did you run test #5 with the thermostat and boiler connected? Especially getting 0V for the thermostat is very suspicious. Even without a thermostat connected it should show a voltage above 0. Your readings either indicate a short-circuit on the thermostat wire, or a problem of the thermostat interface of the gateway. Given that your thermostat is showing an error, it must be getting power. That contradicts with a short circuit.
Did you go through the tests described on
http://otgw.tclcode.com/debugging.html? In addition you may want to do a visual inspection of IC1. Make sure that pin 17 is properly in the socket and not bent so it doesn't make contact. If that looks OK, please check the voltage across R5 (assuming you have a volt meter).
Re: Thermostat disconnected error
Posted: Sat May 30, 2015 1:38 pm
by rkoebrugge
Results of test 5 are in the third printscreen. Voltages are both 0 volt.
I don't have a vol or multimeter, so I have to check if I can verify the connections.
Re: Thermostat disconnected error
Posted: Sat May 30, 2015 4:41 pm
by hvxl
Yes, I can see the results of the test. However, I can't see if the thermostat and boiler were connected when you ran the test. So that was my question.
If you don't have a volt meter, I assume you bought a pre-built gateway. In that case you may consider sending it back. Your description indicates there's something wrong with it.
Re: Thermostat disconnected error
Posted: Thu Jun 11, 2015 7:29 am
by rkoebrugge
I recently received a new OTGW and connected this one.
The boiler is now connected, but I get an error on the Thermostat (Celcia 20) saying Error 203. These messages also come by at the log in OTMonitor.
I don't know why, but I also miss some information (Return water Temperature) from the Boiler which was received with the last OTGW. I received this information before succesfully.
What can I do to solve these issues?

Re: Thermostat disconnected error
Posted: Sat Jun 13, 2015 5:20 pm
by rkoebrugge
Anyone any idea? The error on my thermostat is gone. Even when I disconnect and reconnect it.
The return water temperature is still not visible. In the meantime I connected my OTG to Domoticz, but this does not help.
The OTG had several reboots in the meantime.
Is it possible that this value is not transmitted on the Open Therm protocol/communication, because the boiler is off for several days of shining weather outside!
Re: Thermostat disconnected error
Posted: Sun Jun 14, 2015 6:09 pm
by hvxl
The screen shots you provided don't show any problems.
The reason you don't see the return water temperature is that the Celcia 20 doesn't need that value for its heating algorithm, so it doesn't ask for it. With your first gateway (that had a broken thermostat interface), the gateway took charge and did request this value. So we know your boiler supports the Data ID. To get that information again, you should add Data ID 28 to the list of Data IDs the gateway requests instead of unsupported ones: AA=28.
In future please include logs as plain text rather than screen shots.
Re: Thermostat disconnected error
Posted: Tue Jun 16, 2015 11:05 pm
by rkoebrugge
I have to look for a way to add this Data ID to the supported Data ID's. I can't find an option in OTMonitor for this?
I'm trying to get this solved in Domoticz also, this will be my host system for logging and setting values (like the Setpoint) through my network. I hope someone at the dutch Domoticz forum on Tweakers.net can help me on this item.
Re: Thermostat disconnected error
Posted: Wed Jun 17, 2015 6:05 pm
by hvxl
This is just a one-time configuration. The gateway stores it in EEPROM, so it will survive a reset/power-cycle. It doesn't sound very useful to me to request support for this in Domoticz. To make this configuration with otmonitor, press F7, type "AA=28" in the "Free format command" box and press "Send".
Re: Thermostat disconnected error
Posted: Wed Jun 17, 2015 9:46 pm
by rkoebrugge
This works perfect! Thank you very much

Re: Thermostat disconnected error
Posted: Wed Jul 01, 2015 7:50 pm
by rkoebrugge
Is it possible to request the Remote Setpoint also? I can't find the Message Id for this?
Re: Thermostat disconnected error
Posted: Sat Jul 04, 2015 1:38 pm
by hvxl
It's completely unclear to me what you are looking for. The AA command is used to request information from the boiler. The remote setpoint override is something that you provide (via the gateway) to the thermostat.
Here are a few suggestion that may help you get what you want:
- The PR=O command will report the override setpoint the gateway is requesting.
- The actual opentherm message that requests the remote override has ID 9.
- Once the override is in effect, the room setpoint message (ID 16) reflects that.
Re: Thermostat disconnected error
Posted: Fri Jul 10, 2015 3:36 pm
by rkoebrugge
I was hoping that the Remote override setpoint was also a setting that was saved in the EEPROM. And that I could set it.
As I mentioned I use Domoticz to control the OTG. I do get all the values correct and have a setpoint option to set. But when I change this value, then the Celcia thermostat overwrites the value again. I was thinking that I'd have to use the remote override setpoint, so that I can set a setpoint, which is not controlled by the Celcia, but by Domoticz.
Re: Thermostat disconnected error
Posted: Sun Jul 12, 2015 12:18 am
by hvxl
I'm having trouble to understand what you are trying to convey. The original idea was for the gateway to temporarily override the normal schedule of the thermostat. I wanted a manual change on the thermostat to cancel the override. Because it's only a temporary situation, the override setpoint is not stored in EEPROM. Whether something is stored in EEPROM is only relevant when the gateway gets reset anyway. And that should normally not happen for months.
My understanding is that setpoint changes programmed into the Celcia will not cancel a remote override setpoint. Is that not true in your experience? Or are you saying that initially setting the override setpoint on the Celcia works, but if you later change it that doesn't stick? Do you have logs that show this behavior (OTmonitor logs that is, I don't know what to do with Domoticz logs)? Maybe a similar method is required as for the iSense, where the gateway first clears the old setpoint before setting a new one.
Or does the override not work at all? Do you ever see the "TELEFOON" indication on the screen of the Celcia? Did the gateway correctly detect that it is dealing with a Celcia (PR=R returns: PR: R=C)? If not, try issuing an FT=C command.