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Why your minisplit is likely not “modulating” at all

user-1137156 | Posted in Energy Efficiency and Durability on

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.
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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