Alternatives to MHK1 for minisplit?
We’ve had a three-head Mitsubishi Mr. Slim system for about a year now, and we’ve noticed that it takes a fair bit of fiddling to get the unit to hold a set-point. The necessary offset in heating mode is something like 8 degrees F, varying with the outside temperature. During the shoulder seasons, it seems like we pretty much have to cycle the unit off and on or it will overshoot. I understand that the indoor units’ temperature sensors measure essentially the air near the ceiling, so some fiddling is to be expected, but it would still be nice if they could be controlled by a separate thermostat that could provide real feedback. Unfortunately, it looks like the only real option is the MHK1https://amzn.com/B008MB3UM4, which is absurdly overpriced compared to conventional thermostats. Any savings from more efficient operation wouldn’t come close to covering the cost of installing three of these things! Is there any other option for setting up a proper thermostat for Mistu minis?
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Replies
Logan,
This issue has been discussed frequently on GBA. In case you missed some of the earlier threads on the topic, here are some links:
Minisplit short cycles only in heating mode
Mitsubishi mini split behaving very differently with external thermostat vs. without
Remote thermostat for Fujitsu mini-split?
Fujitsu wired thermostat dilemma
Mitsubishi wired remote thermostat
M21-JKO-307
which, iirc, is the only way to get a remote temp sensor when using the new wifi/app controller, instead of the mhk1, [as the wifi/mhk both use the same connector on the indoor unit].
hope that helps
also just saw this
http://www.mitsubishicomfort.com/sites/default/files/thermostat_interface_pr.pdf