How to regain remote control after manual change

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How to regain remote control after manual change

Postby texnic » Sat Dec 22, 2018 1:46 am

Question: what is the action that makes OTGW take over the control?

My thermostat: Honeywell Round Modulation
OTGW version: OTGW+OPiZ
Some own code, which talks to OTGW to provide scheduling functionality

Initial situation: everything functions properly, I can read room temperature and set room setpoint via both my code and OTGW web app. The thermostat shows the little "H" symbol, indicating remote control.

My action: adjust the room set point on the thermostat directly.

Resulting situation: the "H" symbol disappears on the thermostat. The room set point and the room temperature are correctly readout by OTGW. However I cannot override the set point anymore.

Desired behaviour: I would like OTGW to automatically regain control after manually changing the room set point on the thermostat. Success is indicated by the "H" symbol appearing on the thermostat screen.

What I tried:
- pressing all sorts of buttons in the web-app; didn't help.
- my code is still running, continuously trying to adjust the set point; in vain.
- rebooting OPiZ with OTGW, then restarting my code. This seems to help.

It seems that rebooting OPi does result in taking over the control, even without re-starting my code, only OTGW code automatically restarts. However, sometimes it seems not to be enough, and my code is also needed, to send some commands (alternatively, commands can be sent via web app). Because the system takes some time to react, I am not fully sure which of my actions actually triggered control takeover.

I would like to know what minimal action actually restores remote control. Ideally, I would like to avoid rebooting, as it is pretty harsh programmatically.
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Re: How to regain remote control after manual change

Postby hvxl » Sat Dec 22, 2018 10:29 am

I don't know how you did your testing, but you have to give the OTGW a little bit time at every step to figure out what is going on. When you set an override setpoint, the "Remote setpoint override" LED starts flashing. When the thermostat then reports a setpoint that is close enough to the requested override setpoint, the OTGW assumes the override is accepted and the LED will light constantly. The OTGW has to keep sending the override, or the thermostat will revert back to its previous setting. If you then manually change the setpoint via the thermostat, the OTGW detects that and stops sending the override. It also switches off the LED.

There is some amount of time between the OTGW sending the override setpoint and the thermostat reporting back the new setpoint. During this time the thermostat will already show the "H" symbol, but the OTGW doesn't yet know that the override has been accepted. If you then already change the setpoint on the thermostat, the OTGW will continue to send the override, but the thermostat ignores it.

So, repeat your test and wait for the LED to stop flashing before changing the setpoint on the thermostat. You should also be able to regain control by setting the override setpoint to 0, and wait for that to be transmitted to the thermostat. After that, you should be able to set a new override setpoint.

If you believe your OTGW doesn't behave like I described, please show a log.
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