Why your minisplit is likely not “modulating” at all
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In other posts I’ve made observation of specified “capacity reduction” of several hyper heat like systems.
Those observations were all based specifications, which are all at 47f. I observed that most offer a 1/3 ratio. some offer a 1/9 or 1/10 ratio. I found this graph of constant speed capacity.
https://www.highseer.com/pdf/Heat_Pump_Heating_Performance_Chart.pdf
This dramatically alters how we must interpret the specification as outside temperature changes. !/3 capacity ratio @ 47f will maintain constant output. NO MODULATION.
There are some multi splits that have a min/max 0f 1/9 or 1/10 which if we started with the 1/3 modulation offer a reduction of 1/3 of nominal output ie an 18k can drop to 6k.
it takes a 1/3 capacity reduction to maintain constant output..
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