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Community and Q&A

Minisplit Inverter Vanes

user-903081 | Posted in General Questions on

I imagine there is a good reason for this that I’m not understanding, so I appreciate folks help.

Mitsubishi inverter vanes will, when actively attempting to reach the programmed temperature, point in the direction you’ve aimed them. (When heating: aimed down toward the floor and at the farthest corner of the room.)

Once that set temperature has been reached, the vanes automatically turn to blow horizontally, regardless where you’ve told them to aim. Why?

If a unit is across from a window, for example, blowing warm air horizontally seems likely to just get blown right back at the unit, where the return air sensor will register the warm air and say there’s no need to heat up.

Is there a reason the unit reverts to blowing horizontally once temperature is reached? Is there a way to override that? Alternatively, how many errors do I have in what I’ve said and why is blowing horizontally just fine?

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  1. GBA Editor
    Brian Pontolilo | | #1

    Hey Jeremy.

    I have no experience with this system, but I'm interested in the answers too. So, I'm giving your post a bump, hoping that another GBA member see it soon.

  2. gusfhb | | #2

    I know in AC mode they will not stay turned down, but I do not think mine care what position the vanes are in in heat mode, but I do not have on that I want to leave down

  3. user-903081 | | #3

    Thank you both.

    I've spoken to a few people with the Mitsubishi systems (and done some searching online) and I'm pretty confident that when in heat mode and the programmed temperature is reached, the units go into an idle where the vanes move to horizontal and the fan blows minimally.

    What I can't find out and cannot understand is why, and if there is a way to override that (and if I should care).

  4. theLEMband | | #4

    Check the remote and see if there are icons turned on directly above the "°F" symbol. The vanes on my unit would not stay where I wanted them until I turned these off using the sensor button on the remote.

    EDIT: nevermind the vanes reverted again.

  5. brcostelloekuehn | | #5

    yes same q! just seems obvious that having the unit listen when i set vanes to point down, even when not “actively” heating, would help circulate the warm air near the ceiling down to where us lowly bodies are… are there no “secret” settings for this?

  6. evantful | | #6

    From my observations using the Kumo Cloud modules to read what the mini split heads in our system are reading temperature wise, it's not when it reaches the set temp but when it blows past it by 2-3 degrees.

    Our FH12 and FH09 will run all day long once they reach the set temp + 1 degree, but once it gets to 2-3 degrees above that the vanes go up and the compressor turns off. I think that's a reasonable function of the system, it's doing what it can to maintain desired temp

  7. PBP1 | | #7

    Don't know why "inverter" is before "vanes". A compressor can include compressor vanes and a wall mounted unit can include louver vanes. "Inverter" generally relates to compressor technology (e.g., variable motor speed).

    1. Expert Member
      Akos | | #8

      Technically the vanes are moved by a stepper motor that is powered from a DC voltage source. To do that, it needs a stepper driver, which is a type of inverter :)

  8. esxmarkc | | #9

    Late to the game here but my understanding is that in cooling mode, once the temperature is reached and if your vane is on the lowest angle there is concern of condensation buildup and dripping from the vane so the system automatically moves the vane more horizontally to keep this from occurring. But I made it here looking for the ‘override’ for this since I’m tired of manually having to keep moving it back down. Anyone figure this out?

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