Opentherm Gateway

[bruine01]

Indeed a wrong cable from the webshop. I opened the connector and changed the wires. Thanks again for your help.

[wjhos]

Back again,
after some time, i picked up my gateway project. I found out that now some new features have been implemented.
However, i still have some questions :
Does the software recocnize the differences between a DS18B20 and a DS18S20. (at the moment i have a NTC, connected to a pic 16F1825.on the serial port of the 16F88, but not as linear as desired)
What are serial commands for setting my Isense to low/medium/high power demand. I cannot find the info on the otgw pages.
Some comments on the OTmonitor :
I can select a temp. sensor for GPIO A, but that should not work.
For the different LED's i cannot select "none" as output, which i can with the GPIO pins
Furthermore it works splendid.

[hvxl]

Does the software recocnize the differences between a DS18B20 and a DS18S20.
Yes. The first octet of the device ID indicates the family. The code behaves slightly different when that's 0x10 versus 0x28.

What are serial commands for setting my Isense to low/medium/high power demand. I cannot find the info on the otgw pages.
There aren't any. The thermostat decides when it needs more power. That's not something the gateway has to tell it. When the thermostat requests a higher power level, the gateway automatically obliges.

Some comments on the OTmonitor :
I can select a temp. sensor for GPIO A, but that should not work.
Have you tried? When you select "Temp sensor" for GPIO A, it should immediately change back to "None".

For the different LED's i cannot select "none" as output, which i can with the GPIO pins
That's correct. What would be the use?

[wjhos]

Yes, you are right about the GPIO pins, i tested with no gateway attached.
Selecting 'none' as output of course has no real meaning, but should be in line with the GPIO , where i can select 'none'.

I am using a Isense; is there a way to switch on the backlight from OTmonitor.
I am planning to mount the GW in the connection box of the Tzerra. Do you know if it is possible to power the unit directly from the boiler ? There must be 24 or so V from the boiler to power the thermostat. It should be available on the HMI bus, but i cannot find any specification.

[grubciu69]

Hi everyone
I am new on this forum. I also built OTG - RS232 version. I have Vitodens 100 (boiler) and iSense AD 289 (thermostat). Most of the options works well, but some do not. What I noticed it yet:

1. In OTG mode the Gateway can not set the clock of the thermostat (automatically or sending a special command)
2. In OTG mode when nothing I set the DHW setpoint controls a thermostat. I can also set a new DHW setpoint in OTG. But what to do to control the thermostat back the DHW setpoint? I cant do this.

For all the advice I will be grateful

[hvxl]

1. This depends on support by the thermostat. The iSense actually only requests the date and time over OpenTherm when it starts. So normally, after you rip the iSense (without batteries) off the wall and place it back a while later, it will ask you to manually enter the date and time. When you do the same with the OTGW in between and all 3 checkboxes under Clock on the Thermostat configuration screen of OTmonitor enabled, the thermostat will pick up the date and time via OpenTherm.
2. Use SW=0.

[tiga]

maybe a stupid question....

i was thinking about buying the gateway, but i was wondering....

i will use it with a remaha avanta and an honeywell chronotherm vision.
i want to manipulate it with domoticz.

when i change the room setoint will it appear on the honywell display??

lets say i change the setpoint from 20 to 21 degrees will it say 21 on the honeywell??

thanks

[hvxl]

I was hoping someone using a chronotherm vision would answer this question, because I don't and so I can't say with 100% certainty. But normally thermostats will indeed update the displayed setpoint when it's changed through the Opentherm interface. In addition, Honeywell thermostats will usually show the Hometronic icon (an "H" with a roof) to indicate that the setpoint was changed remotely.

[Rodio]

maybe a stupid question....

i was thinking about buying the gateway, but i was wondering....

i will use it with a remaha avanta and an honeywell chronotherm vision.
i want to manipulate it with domoticz.

when i change the room setoint will it appear on the honywell display??

lets say i change the setpoint from 20 to 21 degrees will it say 21 on the honeywell??

thanks

Not the same, but ....
I have a tzerra with a iSense display, and when I change the setpoint in Domoticz the temp on the iSense will follow.