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    #31
    The Mitsibushi units that have CN105 connectors have a lot of great options for integration. Tasmota and other ESP32 platforms have support for the serial protocol the indoor unit speaks, and Home Assistant has great integration support for these: https://community.home-assistant.io/...-pro/107007/49

    You can also use this generic library for control: https://github.com/SwiCago/HeatPump or this for integration with ESPhome: https://github.com/geoffdavis/esphom...ubishiheatpump

    You really don't want to hook a conventional thermostat to these units, as the VRF system works best when it knows what the target temp is and the ambient temp in the room. If it it knows both those things, it can vary the cooling/heating nicely without almost any overshoot. But with a home automation system that can talk to a normal smart stat like a Nest or Ecobee, you can read the target temp and ambient temp from them, and then send along that info through the Esphome integration to the heat pump anytime a change happens, and get the nice room UI from the Nest, and still have all the efficiency of a state designed to talk to the heat pump.

    There are other hacks available for Daikin etc... But none of these units are compatible with "normal" thermostats. Why Nest or Ecobee haven't yet implemented direct support for these is a mystery. It's not like any customer loves the Honeywell stats that are generally shipped with these things. But there are good workaround available.

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      #32
      Originally posted by copras24 View Post
      You can integrate any Mitsubishi or Trane (OEM Mitsubishi) mini-split or VRF indoor unit to HS with a T-Stat Interface adapter PAC-US444CN-1 + a 240Vac (primary) to 24Vac (secondary) Xformer + any third-party Z-Wave T-Stat. No cloud service is needed. See attachment.

      I'm using a Trane XL624 t-stat (no need to connect to Trane's Nexia Cloud Services). It integrates with Alexa as any other ZW T-stat.

      http://mylinkdrive.com/viewPdf?srcUr...-US444CN-1.pdf

      https://www.amazon.com/Mitsubishi-El...0947442&sr=8-6

      https://www.amazon.com/TRIAD-MAGNETI...0947534&sr=8-3

      Hope this helps.
      I recently installed a Mitsubishi split system. Here's what I learned.

      I first went with the PAC-US444CN thermostat interface and had all Honeywell T6 z-wave thermostats on hand. I had spoken with Mitsubishi tech support several times to confirm that configuration would work. However, the three different people I spoke with at technical support always added that "not all features would be available," though none could tell me what features I would be giving up. That changed when the Mitsubishi rep showed up to check on the install that was in progress, he provided a little more information. While the configuration will "work," it will not work well, he said. As it turns out, most (perhaps all) wired thermostats perform binary on/off cycles with the Mitsubishi heat pump instead of adjusting the performance of the inverter. So instead of operating at variable rates, rising and falling based on temperature, the wired thermostats would operate the heat pump at either 0 or 100 percent--all or nothing--forfeiting a lot of the efficiency.

      Well, that made sense to me. I gave in and went with the Mitsubishi RF thermostat with Mitsubishi's "Kumo Cloud" and returned the several hundred dollars worth of z-wave thermostats I had purchased. (I still use a couple of T6s for my heating system and love them.) Fortunately for me, the dealer agreed to eat the cost of the change because it had failed to advise me of, and had not been aware of, the limitations of a wired z-wave thermostat.

      Here are the results:
      The Mitsubishi RF thermostats are made by Honeywell and look identical to the T6 z-wave units. While HomeSeer is not yet talking with my Mitsubishi system, it turns out that the cloud solution with scheduling fulfills 95 percent of my automation needs. And my electric bill reflects the savings created by the heat pump inverter. Admittedly, I have trouble with being forced go to the cloud to control something in my own home, and I would like more control via HomeSeer. But life is full of trade-offs, and in the larger scheme of things, this trade-off has not been that bad for me.
      --Dennis

      Comment


        #33
        Dennis,

        The PAC-US444CN (T-Stat Interface) does NOT make the inverter system operate as a conventional system with 0 or 100% capacity. If proper settings are adjusted via DIP Switches on the PAC-US444, and the T-Stat is adjusted for 2H/2C, the system will operate with variable capacity as intended. The interface monitors the Y1/Y2 or W1/W2 signals simply to know how close to Set-Point the room-air temp is. if the Y2 or W2 signals are energized, the system will operate at full capacity. If only the Y1 or W1 are energized (meaning that room temp is close to set point), the system will modulate capacity to stay in that zone for as long as possible. If Y1 or W1 de-energize (no voltage), then the PAC-US444 just learned what the Set Point is on the third-party thermostat.

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          #34
          Originally posted by jgreenberg01 View Post
          I know this has been discussed before, but my question is a little different.

          I am going to add A/C to my garage, and a mini-split is my preference because I'm not sure where I'd put an air handler for a regular unit. Plus mini-splits are cheaper!

          While those remotes they include are fine, I also want to control it through HS4. Some of the manufacturers offer "smart" solutions which seems to always require using their proprietary app. Others allow a 3rd party smart wi-fi TStat, but they also require a cloud connection.

          This is a new installation so I can use any brand I want, but the manufacturer websites aren't clear on adding a wired TStat.

          Yes, I know I can use an IR blaster, but that doesn't provide 2-way communication.

          Don't want to go the wi-fi route unless there's one that does not require an internet connection and will integrate with HS4. Another potential issue with wi-fi is the manufacturer messing with their API (like what just happened with MyQ last week that required days to get fixed!).

          My preference is to find a way to use a Z-wave TStat like the Honeywell I use to control my Carrier central air unit.

          I've also had an A/C contractor over and he's looking onto it for me, but it's been 3 days and no word from him yet.

          I suspect that Carrirer or Mitsubishi has some sort of module that let's you hardwire a TStat but I can't find it easily on the interwebs. So before I call their tech support, wait 45 minutes on hold, then try to interpret what someone from another country with marbles in their mouth is mumbling, I thought I would see if anyone here has figured this out already.

          Thanks in advance for any help!
          You can install a regular Tstat for most split units. Check your installation manual for details.

          Comment


            #35
            Originally posted by copras24 View Post
            Dennis,

            The PAC-US444CN (T-Stat Interface) does NOT make the inverter system operate as a conventional system with 0 or 100% capacity. If proper settings are adjusted via DIP Switches on the PAC-US444, and the T-Stat is adjusted for 2H/2C, the system will operate with variable capacity as intended. The interface monitors the Y1/Y2 or W1/W2 signals simply to know how close to Set-Point the room-air temp is. if the Y2 or W2 signals are energized, the system will operate at full capacity. If only the Y1 or W1 are energized (meaning that room temp is close to set point), the system will modulate capacity to stay in that zone for as long as possible. If Y1 or W1 de-energize (no voltage), then the PAC-US444 just learned what the Set Point is on the third-party thermostat.
            How frustrating, then. Obviously, I am no HVAC expert, and based on what you are saying neither was my dealer and the Mitsubishi rep. This makes me want to scream. It is maddening when the folks selling a product don't know the product they are selling.

            Would you share where did you find that info? I would like to present it to my dealer and have a little discussion.

            Thanks.
            --Dennis

            Comment


              #36
              Originally posted by GadgetHome View Post

              How frustrating, then. Obviously, I am no HVAC expert, and based on what you are saying neither was my dealer and the Mitsubishi rep. This makes me want to scream. It is maddening when the folks selling a product don't know the product they are selling.

              Would you share where did you find that info? I would like to present it to my dealer and have a little discussion.

              Thanks.
              --Dennis
              Dennis, your rep was mostly correct. Going with a 2 stage thermostat wiring and the thermostat adapter does give the system more than just on/off, but still not as efficient as the scroll inverter can operate. It's a matter of degree. For me, the benefit of maximum efficiency and comfort from a VRF style system is something I didn't want to compromise on. The kumo system gives you that.

              Both hubitat and home assistant have kumo plugins, and you can use those platforms to bring in data to homeseer.

              Comment


                #37
                Originally posted by silverton38 View Post

                You can install a regular Tstat for most split units. Check your installation manual for details.
                This is not what I am finding. My recycle bin is full of downloaded installation manuals from various manufacturers that make no mention of connect external TStats.

                Through speaking with the good folks on this forum, as well as the HVAC vendors my company uses to install the units in the homes we sell, I have only identified 2 manufacturers thus far that will absolutely do this.

                They are: LG & Trane (Mitsubishi).

                There are lots of manufacturers that will allow a "smart TStat" connection through wi-fi, which is what I specifically do NOT want to do. I am trying to avoid getting into a situation where the only external control is through a cloud service.

                If you do know of another brand that does this, I would be grateful if you would share.

                For now though, it will be LG or Mitsubishi, depending on what discounts - if any (there's some advantages to being in the new home biz!) can get me.

                Comment


                  #38
                  While the Kumo service is technically cloud based, the Home Assistant plugin can be configured to talk to it locally, but it does require cloud connectivity for the initial setup. It works well.

                  The other approach is what I referenced earlier, and use a esp32 to connect directly to the CN105 connector on the Mitsubishi indoor units. This allows you to completely replace any cloud connectivity solution, and control the units purely through local automation. You can then use any thermostat supported by a plugin to then send commands to the VRF unit through the automation.

                  We love our Mitsubishi units! The controls are a bit weak, but there are many options that support local control and do not require efficiency compromises.

                  Comment


                    #39
                    Originally posted by fresnoboy View Post
                    While the Kumo service is technically cloud based, the Home Assistant plugin can be configured to talk to it locally, but it does require cloud connectivity for the initial setup. It works well.

                    The other approach is what I referenced earlier, and use a esp32 to connect directly to the CN105 connector on the Mitsubishi indoor units. This allows you to completely replace any cloud connectivity solution, and control the units purely through local automation. You can then use any thermostat supported by a plugin to then send commands to the VRF unit through the automation.

                    We love our Mitsubishi units! The controls are a bit weak, but there are many options that support local control and do not require efficiency compromises.
                    I saw your earlier post referencing an esp32. I've installed pretty much everything in my house myself from electrical to plumbing to video to... you name it. Replacing the original central A/C TSTat with a Honeywell T6 Pro was easy enough, but for some reason I'm hesitant when it comes to messing with a new mini-split installation.


                    I'm going to let the pros install it, but I will ask about the esp32 first as that sounds like the most flexible non-cloud option.

                    My guess is that they're gonna give me the "deer in the headlights" look when I ask though

                    Comment


                      #40
                      Originally posted by jgreenberg01 View Post

                      I saw your earlier post referencing an esp32. I've installed pretty much everything in my house myself from electrical to plumbing to video to... you name it. Replacing the original central A/C TSTat with a Honeywell T6 Pro was easy enough, but for some reason I'm hesitant when it comes to messing with a new mini-split installation.


                      I'm going to let the pros install it, but I will ask about the esp32 first as that sounds like the most flexible non-cloud option.

                      My guess is that they're gonna give me the "deer in the headlights" look when I ask though
                      They are guaranteed to not understand an ESP32. Take a look at a Kumo WiFi adapter (PAC-USWHS002-WF-2) and see if you can't find an integration pathway for your system that is local like the Home Assistant one. Good luck!

                      Comment


                        #41
                        I'm still working my way through this, but has anyone actually used the PAC-US444CN-1 interface with a Mitsubishi mini-split?

                        I'm getting conflicting answers as to whether the RF remote will still work when using an external TStat. The manual has this:

                        Click image for larger version

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                        But I've had others tell me otherwise.

                        This is incredibly frustrating!

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                          #42
                          I have an MXZ condenser with 5 MSZ wall units. I purchased 5 PACs and 5 Ecobees to automate each zone, but so far only have 2 zones installed at this time. I can tell you a few things:
                          - Don't use the remotes if you have the PAC installed on that wall unit. I can confirm - in my experience - they do not work together properly.
                          - I do use the remotes on the three zones that do not have the PACs installed yet. They work.

                          Overall, Ecobee/PAC works - mostly. I am having one problem that I'm still sorting through, I don't think it's related to still using the remotes on some units. I believe it's related to how the Ecobee is configured & PAC switches are set.

                          When it is first turned on everything works as expected - heating/cooling starts, if setpoint is not reached, stage 2 kicks in, setpoint is reached and it turns off. All fine and good. It's a vacation beach house & it experiences extreme temperatures both hot and cold, and the unit is a bit undersized. The problem - if it is very hot or cold outside, the unit struggles to reach setpoint and runs for hours. It drops back to Stage 1 after several hours, and then it will definitely never reach setpoint. I have not been able to pinpoint how long it runs at Stage 2 before 'resetting' to stage 1 - this happens overnight, or during the day while we are not home. Turning all units/stats to OFF, and then turning them back on solves the problem. It works as expected, with Stage 2 kicking in properly.

                          Since it's a vacation home, it has not been a priority to figure this out, but I'm working on it. I suspect DIP switch settings on the PAC may correct this problem.

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