OTGW without thermostat

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OTGW without thermostat

Postby Mario from Spain » Fri Oct 28, 2016 11:00 am

Hi.

Two days ago I finished building my OTGW kit bought at the shop and I spend a lot of time reading and searching the forum but can't find the answers or the answers I found are not working for me.

I want to use it, without a thermostat, controlled by homeseer (I want homeseer to be the on/off thermostat using the temperature sensors in various points of the house) via HTTP or MQTT. I know Homeseer will have to calculate the the necessary parameters (like Control setpoint, CH-enable, Max Relative Modulation level).

I have my OTGW connected to a Remeha Calenta via wifi with an ESP8266. Apparently the gateway is receiving data from the boiler but I can't send commands to it. Seems like the boiler just ignores these messages.

If I try to change the setpoint (sending "CS=11.00", "CS=11,00" or "CS=11" from otmonitor Miscellaneous screen) it doesn't changes and can't see in the log a "Response: "CS: 11.00" or any other answer:
Image

In this same screen the operating mode appears as Unknown and if I press Gateway or Monitor buttons it doesn't changes.
Image

May be my issue is related to this viewtopic.php?f=75&t=10857 but in my case is not intermittent issue, I already tried resetting the gateway and the issue persists.

At this point I'm lost. I don't know if the gateway is working fine or if homeseer can act as a thermostat and how (a din't look in detail at hot to send Control setpoint, CH-enable, Max Relative Modulation level) but first I don't know if my actual problem is a use/hardware/firmware/configuration issue and if I should dismount the OTGW from where it's mounted to follow the Troubleshooting section.

In the docs regarding stand-alone operation (http://otgw.tclcode.com/standalone.html) I can't find information about using it without thermostat (other than the considerations about the complexity of making a program to control central heating), just in the introduction I can see "Support modulating and on/off thermostats, or even no thermostat at all".
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Re: OTGW without thermostat

Postby hvxl » Sun Oct 30, 2016 2:46 am

With a chance that things would just work, it was worth the shot to try the full setup. But now that you found it doesn't, I suggest to go back to a simple configuration and get that to work first. So, just start with the OTGW and the boiler. Whether you do that by taking the gateway to your PC, or bringing a laptop to the gateway is up to you. Once you got that working, add the ESP8266 and check again. Then finally introduce homeseer.
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Re: OTGW without thermostat

Postby Mario from Spain » Sun Oct 30, 2016 11:30 am

hvxl wrote:With a chance that things would just work, it was worth the shot to try the full setup. But now that you found it doesn't, I suggest to go back to a simple configuration and get that to work first. So, just start with the OTGW and the boiler. Whether you do that by taking the gateway to your PC, or bringing a laptop to the gateway is up to you. Once you got that working, add the ESP8266 and check again. Then finally introduce homeseer.


Thank you very much for answering.

Right now, and after many hours of thinkering and tinkering, I found the cause of the gateway apparently not answering back to otmonitor.

Just for reference and for others in the same situation, I write here exactly what happened (with some keywords to make it easy to find):

My serial connection to the OTGW was established with a serial to TCP connection using a ESP8266 module. I used an Itead's Sonoff module with an ESP12 and the ESPEasy firmware with a module called "Serial Server" (similar to SER2NET). otgmonitor didn't received answers because, by default, the ESPEasy firmware uses the serial port TX on the ESP12 for debug and logging, so it sends login and debug information instead of the data it receives on the TCP port and otmonitor doesn't understand it (and doesn't displays either, so you think it's receiving nothing).
To let ESPEasy forward the received data on the TCP port to the serial port is necessary to turn off logging on the serial port:

Image

Now otmonitor is receiving data from OTGW and can interact with it.
I must now understand what is receiving as in monitor mode it's not displaying anything useful and in Gateway mode there are loads of "Error 03". Maybe it's because there is nothing connected to OTGW's thermostat clamps?

Image

I'll let you know my advances...
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Re: OTGW without thermostat

Postby Mario from Spain » Sun Oct 30, 2016 11:43 am

I adjusted the Reference Voltage to 1.667 and it's not giving the error 03 anymore :-)

Image
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Re: OTGW without thermostat

Postby hvxl » Sun Oct 30, 2016 3:48 pm

In monitor mode, the OT signals from thermostat and boiler are directly connected to each other. As the name says, in this mode the gateway only monitors the traffic, but doesn't change it. If you have no thermostat (the OT master) connected, there is no traffic. In gateway mode the OTGW can inject OT messages in the absence of a thermostat. So in your case you should definitely run in gateway mode.

By the way: Your images don't show up for me. Perhaps you can upload them as attachments to the message, rather than using an external server. That way they will also continue to be available in the future, even when the external server goes away or expires the images.
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