Request for Energy-Monitoring Data on Single-Zone Mitsubishi Minisplit
I posted about a year go with this post: High December electric bill with Mitsubishi heat pumps. I wanted to follow up with all that I’ve learned, as well as put out a request for data others may have.
After many conversations with my installer and their conversations with Mitsubishi, it turns out that the multi-zone units change their compressor frequency as a result of outdoor temperature. I was clearly seeing a big jump in power consumption once outdoor temps hit about 36F. My two 3-zone outdoor units would more than double their electric consumption from about .80 kW/hr to ~ 2kW/hr. I’ve attached a picture of this happening as the temperature dropped below this threshold.
The installer is working with Mitsubishi to revamp my system to only run on single-zone heat pumps. It seems like this is going to happen as I have provided them a lot of my own data as well as building science literature in support of this change. The efficiency / modulating abilities of these multi-zone heat pumps is not at all impressive.
My question to this community is if anyone has similar data to mine, but for single-zone Mitsubishi heat pumps? I’d like to know whether this bump in compressor frequency (and in turn, electric consumption) is also typical for these single-zone set-ups. I have seen others’ monitoring data for non-Mitsubishi single zone heat pumps, but to make a good apples-to-apples comparison, I’d love to see this data specific to Mitsubishi units.
Thanks to all, especially the moderators, for helping with this journey.
GBA Detail Library
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