CS vs MM

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thunderbird
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CS vs MM

Post by thunderbird »

Hi, My boiler does not support a lot of OT messages. But luckily the CH=1, CS '(Central Heating Setpoint) and MM (Max relative Modulation) is supported. So I could start my heating system. The HS (Heating Setpoint) is not supported, but it seems that CS overrides the HS.
Now I come to the point what the difference between CS and MM exactly is.

CS seems to be clear, it controls the temperature of the water.

But MM is much more unclear for me. What means 'Max Relative', will the boiler do something between 0% and 'Max'? Relative, relative to what? And next, what is regulated? Temperature seems to be fixed to the given CS. The only thing I can imagine is the pump speed.
I can check the gas usage via the smart meter, but I do not see a relation between CS (or MM) and the usage.
hvxl
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Re: CS vs MM

Post by hvxl »

See here and here for some recent posts where I explained these parameters.
Schelte
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