Ductless minisplit aftermarket controller: D6 pro vs Sensibo vs mhk1 vs…
Hi all,
I am in a well insulated home but my mini splits (Mitsubishiu MSZ) are acting as many have observed by pooling hot air and not effectively monitoring the temp in my living space. I would like to monitor and control the temp from across the room remotely. I’ve looked at options and cannot come to a conclusion, do people have strong opinions on any devise?
My priorities in order are: effectively maintaining the temp at the location of the new devise, reliability, wi-fi/smartphone synch, and lastly being battery operated (if I have to plug it in so be it).
I can do line of sight to both my mini splits but it would be better if I could go around a corner in both instances (our bed is not line of site but there are options). The home is small so the overall distance wouldn’t likely be over 30 feet.
Thanks for any feedback. I guess this is too much a niche product for the usual shootout review. -Todd
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I bought a Sensibo for the same reason. It doesn't work. There is a belief out there, and I don't remember whether this is supported by Sensibo or not, that the Sensibo has a thermostat. It doesn't. It has a temperature sensor, but it's for display information only. All the Sensibo does is send setting commands to the heat pump (just like the factory remote). The indoor unit of the heat pump still decides whether it needs to provide heating or cooling based on its internal thermostat. I would guess the same would be the case for competing brands of "smart" controller. It's hard to imagine how any one of these devices could hack into the onboard heat pump controller and override the internal thermostat. In theory, I guess if the smart controller sensed that the heat pump was not keeping up, it could send a command to change the temperature setting. There would a huge lag in response using this strategy, and I see no evidence that my Sensibo is doing anything like that.
You need to use the Climate React feature. You can bracket a high and low temperature (via Sensibo's temperature sensor), which will then send a command that will control mode/fan speed/set point.
Essentially: If Sensibo temperature says 68F, set split to 74F heating, high fan. If Sensibo is 72F, set split to 70F heating, auto fan. It'll then ping pong between those settings. Not perfect but it's possible. It's based off Celsius so there isn't a corresponding Fahrenheit for every degree.
Thanks for the tip. I will give that a try, but I'll be surprised if that crude control does any better than the minisplit is doing on its own.
I would think that would destroy the efficiency you get from modulation. Doing step changes to the setpoint will cause the unit to ramp up and then shut off.
The Mitsubishi protocol allows setting a remote temperature, and this is what the mkh-1 does.
Ill throw my Honeywell D6 experience. It also doesn't work. You loose important functionality like vane control (and will override whatever setting you had putting the vanes in a sweeping motion), and like the Sensibo doesnt use it’s temperature sensor to actually benefit unit control.
Most importantly though it’s unreliable in the commands it sends to the head unit. It uses IR like the remotes and doesnt always get it right. Which then becomes a hassle of getting it to issue the command again.
The MHk1 would better serve you, or the the Kumo Cloud dongle. Kumo cloud has come along way in reliability, it use to be glitchy but now it’s pretty rock solid(iOS app wise at least) Installation is pretty straight forward. I’m currently in Mexico and check on my minis splits In upstate NY daily via the app
My biggest beef with the IR based units (Sensibo) is that the min split head beeps when the setting get changed. Make sure you can turn this off on your unit otherwise it will get annoying.
The climate react does work well but there is no scheduling option, you are limited to a single set point.
I think overall the better strategy is either the remote unit from Mitsubishi or go with the relay module and standard thermostat. I'm starting to lean for the relay module as it gets you out of proprietary hardware, and you can easily change things down the road.
It does have tie-ins with IFTTT which I have experimented in the past. Before climate react I would use my ecobee + sensors temperature reading to send the Sensibo command via IFTTT. It worked well enough but not great at narrow tolerances. I tend to try and keep a 1 degree swing and it's just not meant for that. If you know your system's needs based on outdoor weather, you could also send IFTTT commands like that as well (if outside below 30F, set fan to high).
I ended up getting the Fujitsu remote unit as well- it works well given my situation that I really only use them for AC and shoulder season. My gripe is in auto mode (quiet), it won't kick in to high fan unless there is a 5F degree swing. That's unacceptable to me. I still use the Sensibo to control the unit even with the hardwired thermostat that it gets the temperature from.
I was thinking about the Sensibo as well for our four mini-splits, as getting four MHK1's gets expensive. So they don't control the vanes? I had a chat going with them, and the person wanted to know what I wanted to control that the Sensibo doesn't... Johns3k - Thanks for the tip about Climate React.
For now, I leave the fan manually on #2 instead of auto, and looking at the IotaWatt power draws, it's very consistent, and cycling has all but stopped (just the defrost cycles every now and them).
So you can control the swing of the vanes via the remote. You can't cycle through vane angles like the remote. However, it will keep the current position of the vanes as long as you don't switch between cooling and heating- at that point they will revert to their default behavior for each mode. If you go heating-off-heating, at least with my Fujitsu's, it'll keep their current position.
It does have tie-ins with IFTTT which I have experimented in the past. Before climate react I would use my ecobee + sensors temperature reading to send the Sensibo command via IFTTT. It worked well enough but not great at narrow tolerances. I tend to try and keep a 1 degree swing and it's just not meant for that. If you know your system's needs based on outdoor weather, you could also send IFTTT commands like that as well (if outside below 30F, set fan to high).
I ended up getting the Fujitsu remote unit as well- it works well given my situation that I really only use them for AC and shoulder season. My gripe is in auto mode (quiet), it won't kick in to high fan unless there is a 5F degree swing. That's unacceptable to me. I still use the Sensibo to control the unit even with the hardwired thermostat that it gets the temperature from.
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I have the MHK1 on mine, it was a game changer. Unit modulates nicely to maintain space temp without short surges like it did with the built in sensor.
It's wireless (not wifi) so you can experiment with finding the optimal location. And it provides a real remote temperature reading so modulation works great. The only thing it lacks is smartphone integration, which for me was actually a plus. Smart devices tend to go unsupported long before the hardware lifecycle is done.
Kumo cloud with the remote temp/humidity sensors would work too. But I haven't tried it.
The sensiboo strategy of just cranking the setpoint up and down will harm efficiency, to what level I'm not sure.
There is also the thermostat connection kit, which appears to be well implemented and tries to do some modulation even with only 2 stages of input. You could use this and your favorite Nest or Ecobee stat. It looks at the rate of change of temperature and will slowly ramp till it's winning, and then hold the modulation level.
https://meus.mylinkdrive.com/sfiles/Application%20Note%203044%20-%20Thermostat%20Interface%20Sequence%20of%20Operations.pdf
My pick is definitely the MHK1 if you can live with the looks. It isn't' dependent on wifi (it has it's own low power wireless connection), has feature rich interface (multiple fan speeds and vane positions), scheduling, and first party support. Only downside is the slightly dated appearance which isn't bad.
There is a MHK2 on the way, based on the new T6 thermostats (I think).
Some photos of it available at the FCC website: https://fccid.io/HS9-MRCH2/External-Photos/External-Photos-20190304-v1-LANCER-CONTROLLER-EXHIBIT-4-1-External-Photos-4208211
Also, the MHK1 should be usable with the Redlink internet gateway to get control of the thermostat via Honeywell's mobile app.
I had the same problems with my Fujitsu until I got the wired thermostat. It can be set so that it really is a thermostat, sensing the temperature where you put the thermostat instead of at the indoor unit up by the ceiling. It works for me.
Thanks for the feedback everyone. This was a great thread.
MHK2 manuals are up on the website:
http://meus1.mylinkdrive.com/item/MHK2.html
New entry coming into market - https://getmysa.com/
I've been pretty happy with the Sensibo device tbh, the Mysa looks a little nicer with the temp display.