MQTT topic chwaterdeltat is zero or incorrect

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aengen
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MQTT topic chwaterdeltat is zero or incorrect

Post by aengen »

My expectation and from the source code I think the intended functionality is that: chwaterdeltat = boiltemp - return temp
However the MQTT messages (all with similar time stamps) do not support this assumption. Since I have some other issues with data that is seemingly out of sync, I hope this may lead to a root cause.

example :
boiler = 60
return = 25
delta = 0 (a value of 2 has been observed )

Messages:
21:09:26.897316 Command (via websocket): PS=1
21:09:26.911531 PS: 1
21:09:27.113957 00000000/00000000,0.00,00000011/00000011,0.00,0.00,0.00,28/25,0.00,0.00,1.60,0.00,0.00,0.00,40.00,0.00,6.00,25.00,0.00,0,60/30,85/0,60.00,70.00,00000000/00000000,0,0,13035,0,0,32583,6510,0,0,687

Status:
19 25 Read Boiler water temperature 60 60.00
78 120 Read Burner operation hours 144 6510
74 116 Read Burner starts 144 13035
01 1 Write Control setpoint 58 59.00
7B 123 Read DHW burner operation hours 144 687
77 119 Read DHW burner starts 155 32583
38 56 Read DHW setpoint 59 60.00
30 48 Read DHW setpoint boundaries 47 60 30
1A 26 Read DHW temperature 60 0.00
39 57 Write Max CH water setpoint 359 60.00
0E 14 Write Maximum relative modulation level 23 5.00
1B 27 Read Outside temperature 59 6.00
1C 28 Read Return water temperature --- 25.00
00 0 Read Status 1 00000001 00001010
aengen
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Re: MQTT topic chwaterdeltat is zero or incorrect

Post by aengen »

Apparently my boiler stops sending the return temp.When I request it with PM=28, I can see the updated value , that is also updated in otmonitor. The confusing part is that the (obsolete) return temp does show up in return message after issuing PS=1. And also in retained MQTT messages.

could otmonitor have a feature to periodic poll values from the boiler?
hvxl
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Re: MQTT topic chwaterdeltat is zero or incorrect

Post by hvxl »

What do you mean, "my boiler stops sending the return temp"? A boiler never takes the initiative to send any message. Something has to ask for it. Either the thermostat or the OTGW. As documented, the PM=28 command of the OTGW only requests the information once. For polling periodically, use the AA=28 command. As always, if something doesn't work as advertised, provide a log.
Schelte
aengen
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Re: MQTT topic chwaterdeltat is zero or incorrect

Post by aengen »

Schelte, thank you for your response and emphasising this point.

Otmonitor is working as specified. That was my implicit conclusion in my previous post. Now it is also clear to me that my boiler is working as expected.

I think the observed behaviour in my first post can be explained by the assumption that an initial poll of a certain value (e.g. return temp) by the thermostat is successful, and later my thermostat stops polling this value. Therefore there are no actual values for these values to be reported in Otmonitor. A personal to do is that I will look in the logs to see whether there is a clue why the thermostat stops polling (e.g. boiler sometimes responds with an unknown data Id).

Nevertheless a user of Otmonitor could be interested in these actual values (e.g. for MQTT) that are not regularly polled by the thermostat. Therefore some polling mechanism is my feature request. Either by a setting in Otmonitor or via a MQTT action (my preference). If the AA command could be used for polling (e.g. the return temp) by OTGW automatically, could you please explain this in more detail?

Could the addition of a MQTT action in Otmonitor that passes through (1:1) OTGW commands be a solution for this? So: MQTT to send an action e.g. {"cmd": PM, "value":18} and Otmonitor would interpreted this and send "PM=18" to OTGW.
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