Hi Tim,
first: what a beautiful setup, a feast for the eyes!
then: how old are these systems that you have installed?
My first instinct, whatever the age of these systems are is that I myself, too, would be inclined to leave them unplugged. Sounds like your studio space is an excellent environment just as it is.
Then, in my experience there are two main issues I regularly encounter out in the field (I maintain and service 100+ of these systems). The first is user inconsistency, a) accidentally unplugging the system from the power outlet, b) "forgetting" to fill up water. Sometimes both or any of these inconsistencies can change the RH under the grands so drastically that it'd basically be better if there were no systems installed at all (!)
Now, a well maintained system is of excellent help regarding this first issue. But no level of regular user maintenance can help with the second issue: as systems get progressively older, according to my own personal and anecdotal experience, the RH reading in the humidistat can become… well, less than optimal over time. I've done some measurements, and sometimes older systems tend do their zig-zaging around a suboptimal RH level, which throws the whole stabilization idea off. I don't know if this might have something to do with our crazy low Finnish indoor RH during jan-feb (usually <20%) and, respectively, crazy high indoor RH during july and august (sometimes >75%), but the RH measurement sensor inside the humidistat seems to get thrown off with increasing age.
I usually explain the situation to my clients (this problem occurs well after the warranty has expired) and most often they are willing to 1) replace the humidistat controller unit (if it's the newer version), or 2) replace the whole system (if the existing system if of the old kind with hard-wired, unpluggable cables running to the different parts).
If anybody has had experiences resembling these of mine, or opposite ones, please feel free to confirm or deny.
Anyways, I would personally leave these units unplugged, FWIW. Just my two cents.
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Patrick Wingren
Jakobstad, Finland
patrick@wingrenpianistik.fi
0035844-5288048
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