OT Thing - An OpenTherm-WiFi Gateway with integrated OT master & slave

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184

Please supply:

  • Brand & model of boiler & roomunit
  • OTthing firmware version
  • status JSON (http://[OTTHING-IP]/status)
  • configuration JSON (http://[OTTHING-IP]/config)
  • OT status JSON (http://[OTTHING-IP]/otitems)
  • OTthing log
185

what is “DHW blocking” option?

It is an option given to the boiler, behaviour depends on it. Usually this will inhibit the heating circuit while delivering hot tap water

what is “member ID” option?

A supplierdependant value sent to the boiler, some boilers need a specific ID from the master

what is the difference between the heating surface exponent in Dimensioning and the gradient in Heating curve? Should I set them on the same value? I searched for information about it, I know understand how to set the heating curve but I from what I read those parameters seems similar.

Surface exponent depends on the type of heating (floor, radiators, …), it describes the physical behaviour of it (amount of radiation, convection, …). It can be found in the datasheets of your heating elements.
The gradient depends on things like insulation, areas etc.

I read on the project page about the PI controller, I (basically) understand the theory, but how I do know which values I have to put? Or shoud I leave it off for now?

You can find it out empirically, but also on the internet is a lot of information how to tune PI controllers

186

Thanks a lot for your explanations.
I tried DHW Blocking, seems like on my boiler it deactivates totally DHW production.

187

After manually updating the firmware to 2.35, it seems to have resolved the issue again. :slight_smile: I have another question: after connecting to the digital input, what is it called in Home Assistant? I have several binary sensors and I don’t know which one is for the digital input. Which one should be used? Which one is the digital input? I can check by unplugging it and checking which one is gone, but I don’t have access to the furnace right now.
OK, I think it was enough to connect on/off to the digital input and your controller gives this command to the furnace and turns on the heating?

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188

The digital input was not yet implemented, please see

Digital input can be configured under setup, then a sensor appears in HA.

189

Hi Stefan,

Just received the OTThing, thank you.
Heatpump Remeha toros vision full electric
Room unit, Honeywell touch chronotherm.

But lost how it works, i placed the OTThing between the room unit and heatpump obvioulsy and set the OTThing in repeater mode.

But I dont seem to understand how it works,

For example;
Current temp in room is 19.8

I set the roomsetpoint to 18.5 and mode auto so i expect no heating or cooling will occur

Northing happens, until i switch override ch1 to on. The heatpump starts heating… but why?, the actual temp does not require the start.
What is happening, who is controlling what

What I was expecting and wanted is that the OTThing is in repeater mode, the room unit can set and request and OTThing/HA can monitor or override setpoints for example.

But now, if i dont use the override switch nothing happens and when i set the override it just start heating without a need to.
And in that case, who determines when to stop the heating?, is it the room unit?, is it otthing?

Can you guide me please?

190

try to use OTthing’s master mode and enabled slave interface additionally. If you want to completely shut off on reaching room setpoint use “suspend on roomsetpoint”.