Can't change DHW setpoint

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a g
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Can't change DHW setpoint

Post by a g »

Hi,
I have De Dietrich Baxi boiler without room termostat, I want to use it only with OTGW.

I can receive information from boiler like CH and DHW setpoint, water pressure, etc. Problem that I can't change DHW setpoint, when I use SW nothing changes. Below you can find logs from OTMonitor:

Code: Select all

21:44:25.782302  R80000200  Read-Data   Status: 00000010 00000000
21:44:25.847332  BC0000000  Read-Ack    Status: 00000000 00000000
21:44:26.815198  R80000200  Read-Data   Status: 00000010 00000000
21:44:26.938955  BC0000000  Read-Ack    Status: 00000000 00000000
21:44:27.848594  R80190000  Read-Data   Boiler water temperature: 0.00
21:44:27.913499  B40192619  Read-Ack    Boiler water temperature: 38.10
21:44:29.082324  Command: SW=42.00
21:44:29.245425  R10010A00  Write-Data  Control setpoint: 10.00
21:44:29.310885  BD0010A00  Write-Ack   Control setpoint: 10.00
21:44:29.359130  SW: 42.00
21:44:29.885589  Command: SW=42.00
21:44:29.929983  R80380000  Read-Data   DHW setpoint: 0.00
21:44:29.980400  B40382700  Read-Ack    DHW setpoint: 39.00
21:44:30.032205  SW: 42.00
21:44:30.064971  Command: SW=42.00
21:44:30.141176  SW: 42.00
21:44:31.233504  Command: SH=75.00
21:44:31.287072  R00390000  Read-Data   Max CH water setpoint: 0.00
21:44:31.314833  BC0395050  Read-Ack    Max CH water setpoint: 80.31
21:44:31.407187  SH: 75.00
21:44:31.971838  R80000200  Read-Data   Status: 00000010 00000000
21:44:32.095640  BC0000000  Read-Ack    Status: 00000000 00000000
21:44:32.274690  Command: SH=75.00
21:44:32.407484  SH: 75.00
21:44:32.462282  Command: SH=75.00
21:44:32.532515  SH: 75.00
21:44:33.003108  R00120000  Read-Data   CH water pressure: 0.00
21:44:33.221965  B40120133  Read-Ack    CH water pressure: 1.20
21:44:34.050547  R80000200  Read-Data   Status: 00000010 00000000
21:44:34.108752  BC0000000  Read-Ack    Status: 00000000 00000000
21:44:35.061844  R80190000  Read-Data   Boiler water temperature: 0.00
21:44:35.191224  B40192619  Read-Ack    Boiler water temperature: 38.10
21:44:36.097368  R10010A00  Write-Data  Control setpoint: 10.00
21:44:36.221806  BD0010A00  Write-Ack   Control setpoint: 10.00
21:44:37.125972  R80000200  Read-Data   Status: 00000010 00000000
21:44:37.249669  BC0000000  Read-Ack    Status: 00000000 00000000
21:44:38.160788  R00110000  Read-Data   Relative modulation level: 0.00
21:44:38.221785  BC0110000  Read-Ack    Relative modulation level: 0.00
21:44:38.471358  Command: HW=0
21:44:38.546861  HW: 0
21:44:39.191033  R001B0000  Read-Data   Outside temperature: 0.00
21:44:39.251500  BC01B0F00  Read-Ack    Outside temperature: 15.00
21:44:39.333972  Command: HW=A
21:44:39.438082  HW: A
21:44:40.164925  Command: HW=1
21:44:40.205062  R801C0000  Read-Data   Return water temperature: 0.00
21:44:40.297859  HW: 1
21:44:40.357418  BC01C2633  Read-Ack    Return water temperature: 38.20
21:44:41.252158  R900E6400  Write-Data  Maximum relative modulation level: 100.00
21:44:41.316775  B500E6400  Write-Ack   Maximum relative modulation level: 100.00
21:44:42.267010  R80000200  Read-Data   Status: 00000010 00000000
21:44:42.393451  BC0000000  Read-Ack    Status: 00000000 00000000
21:44:43.313467  R80000200  Read-Data   Status: 00000010 00000000
21:44:43.375691  BC0000000  Read-Ack    Status: 00000000 00000000
Only Control setpoint have Write is it normal? Shouldn't there be Write-Data after my SW? I appreciate every tip because I've been fighting with this for long time.
hvxl
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Re: Can't change DHW setpoint

Post by hvxl »

I may not have considered this scenario when I made that piece of code. It's been a few years, so I really don't remember. And it may be a while before I will find the time to dive into the code again.

Just to be sure, your boiler does report the value for MsgId 6 as 0x0303? The OTGW will only request this data once (if at all in stand-alone mode). If the low byte is 0x00, then the boiler does not support modifying these settings via Opentherm.
Schelte
mwtheplumber
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Re: Can't change DHW setpoint

Post by mwtheplumber »

Not all boilers that claim to be Opentherm fully support Opentherm. I seem to remember some incompatibilities with Baxi boilers as regards to DHW setpoint.
hvxl
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Re: Can't change DHW setpoint

Post by hvxl »

This should be fixed in OTGW firmware version 5.0.
Schelte
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