I realise this is a side issue, but I'm struggling to see the logic of allowing OpenTherm to control the pump speed.
Surely on a boiler with an integral pump, the boiler knows best what pump speed is needed in order to maintain a given flow rate? The thermostat simply needs to say "I need flow at 48 degrees" or whatever.
What leads you to believe that control of pump speed is an issue here?
I reckon, PERHAPS, although the boiler can modulate down to 30 degrees, maybe it's reporting back across opentherm that it'll only go down to 45. Which then forces the Lyric into "low load" mode below that value.
So perhaps the bug isn't what it can do, rather what it SAYS it can do.
You'd need something like this to debug what's going in.
But can't help wondering whether the pump speed thing is a red herring.
P.
Surely on a boiler with an integral pump, the boiler knows best what pump speed is needed in order to maintain a given flow rate? The thermostat simply needs to say "I need flow at 48 degrees" or whatever.
What leads you to believe that control of pump speed is an issue here?
I reckon, PERHAPS, although the boiler can modulate down to 30 degrees, maybe it's reporting back across opentherm that it'll only go down to 45. Which then forces the Lyric into "low load" mode below that value.
So perhaps the bug isn't what it can do, rather what it SAYS it can do.
You'd need something like this to debug what's going in.
But can't help wondering whether the pump speed thing is a red herring.
P.
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