Originally posted by AlexP
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If you have a boiler relay the minimum on-time sets the minimum amount of boiler demand required before the boiler relay will actually turn on. 10% isn't quite enough to turn the boiler on with the default 6 cycles and one minute minium on-time and if your minimum on-time is more the required percentage increases.
The question is why is load scaling scaling the load down by a factor of 10.... I saw that in my frost protection test but I assumed that was due to the very low (5C) set point I was testing at. At my normal set points I'm seeing a load scaling factor more like 2 - EG an individual zone calls for 100%, this results in 50% for the boiler. Load scaling also seems to combine the heat demands of different zones in a semi-additive fashion.
For example one zone only calling for 100% heat causes the boiler relay to be about 50%, but with two zones both calling for 100% heat the boiler relay goes to 100%. While the principle is sound, scaling by up to 10x in some circumstances seems a bit excessive, and I wonder what is triggering that.
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