TSP for Remeha boiler and thermostat

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drut
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TSP for Remeha boiler and thermostat

Post by drut »

Hi!

I'm using OTGW since a while and lately I've rebuilt my CH so it uses only boiler pump.
I was able to set TSP (so boiler-parameter) of minimum pump-speed and I'd like to be able to change it remotely.

Here is the log when I go to Remeha thermostat and check the value of P028 field (TSP) which is 10 (x10 - 100% speed) and change to 7 (x10 - 70% pump speed).
I'd like to do just the same with OTGW.

Any help is appreciated, PM=10 doesn't provide any feedback in log.
A lot of minutes later, randomly, I can see in log that it says TSPs supported amount is 45.

Code: Select all

20:57:24.785240  T000B1C0A  Read-Data   TSP setting: 28 10
20:57:24.842692  BC00B1C0A  Read-Ack    TSP setting: 28 10
20:57:25.839763  T10012D00  Write-Data  Control setpoint: 45.00
20:57:25.875013  BD0012D00  Write-Ack   Control setpoint: 45.00
20:57:26.756896  T00110000  Read-Data   Relative modulation level: 0.00
20:57:26.852193  BC0110000  Read-Ack    Relative modulation level: 0.00
20:57:27.785434  T80190000  Read-Data   Boiler water temperature: 0.00
20:57:27.856187  B401923E6  Read-Ack    Boiler water temperature: 35.90
20:57:28.721632  T100B1C07  Write-Data  TSP setting: 28 7
20:57:28.861630  BD00B1C07  Write-Ack   TSP setting: 28 7
20:57:29.792804  T00090000  Read-Data   Remote override room setpoint: 0.00
20:57:29.867578  BC0090000  Read-Ack    Remote override room setpoint: 0.00
20:57:29.888734  AC0091680  Read-Ack    Remote override room setpoint: 22.50
20:57:30.755353  T800B1C07  Read-Data   TSP setting: 28 7
20:57:30.959664  B400B1C07  Read-Ack    TSP setting: 28 7
hvxl
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Re: TSP for Remeha boiler and thermostat

Post by hvxl »

Maybe you don't fully understand what PM=10 does. The PM command queues a message to be sent to the boiler instead of a message that the OTGW has learnt the boiler doesn't support. With PM=10, it gets a response indicating how many TSP the boiler supports. The OTGW then queues MsgID 11 with TSP-index 0 to be sent instead of the next unsupported message. Next, the OTGW queues MsgID 11 with TSP-index 1, etc. This continues until all the TSPs have been queried. If your boiler supports most messages your thermostat sends, this can take a long time. But it isn't random. In the logs you should be able to find the read requests for all of the TSPs.

The OTGW currently doesn't support writing TSPs. If you want it bad enough, you will have to add it yourself.
Schelte
drut
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Re: TSP for Remeha boiler and thermostat

Post by drut »

Is there a way to add it if I doesn't know a word in assembler?
My boiler is Remeha Tzerra Plus (clone) which in the table has limited support of PM=11 as I understand.
PM=10 indeed gave TSPs supported 45, but it doesn't do the behavior as you described - I didn't see the queries going along after that (or they may have been on new IDs)?

I need it so badly that I even think about adding some other MCU in between just to pass that TSP message.
I mean, do connection like:

iSense <-> OTGW gateway <> other OTGW interface <> BOILER

But I don't know if it will be possible to have two gateways and have second one just to subscribe MQTT topic and pass number between 3 to 10 as one of TSPs.
hvxl
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Re: TSP for Remeha boiler and thermostat

Post by hvxl »

Luckily assembly[*] normally doesn't use many words. So even if you don't know a single word of assembly, there are only about 20 left to learn. And the assembly languages for each type of processor will be different anyway. So even if you did know a different assembly language, you would still have to learn the PIC16 variant. So, not knowing assembly isn't as huge a disadvantage as you might think.

Alternatively you could load the interface firmware into the OTGW and then make it do what you want using a programming language you are more comfortable with.

And yes, it is possible to put multiple gateways in series. But because each gateway causes some delay and the master must receive an answer within a certain amount of time, the limit is around 4 gateways.

[*]: "Assembly" is the programming language, "assembler" is the program to turn the assembly code into machine code.
Schelte
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