Smart control system for ASHP and ERV?
I have heard that smart thermostats, such as Google Nest, are not compatible with these high performance home systems. We have a ducted Mitsubishi ASHP (2 separate air handlers) and a Van-ee ERV. The main floor and upstairs have thermostat and ERV controller wired on the main floor. Basement has it’s own thermostat.
Overall, I want to be able to control the ERV and ASHP from upstairs without having to go downstairs. For instance, if we want to open the windows it seems crazy to have to walk so far to turn the systems off. I would really like to be able to control both from an app.
As someone who cares a lot about interface design, I really want a sleek UI and a well designed control product rather than something that looks like it is from 1995 with a bunch of buttons. I think it is a generational issue but I simply do not understand old outdated tech so I want something that is easy and beautiful to use, think: Apple. But I also don’t want to compromise on the system performance.
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From what I can tell the third party smart thermostats disable the variable speed features of the heat pumps they control. They output states of OFF, LOW and HIGH.
My guess is Mitsubishi cloud interface also disables the variable speed features because when people post power usage data from Mitsubishi cloud systems it dos not show the power usage ramping up and down as expected it seems to cycle on and off.
Walta
Yikes! There must be a better way. I have heard the Mitsu Kumo cloud system is horrendous. I see an issue here with these companies making great hardware but they don’t seem to understand anything AT ALL about software design or user interfaces. This was an advantage of Daikin as they have a great controller and app, but it was not really an option locally for us.
I don’t understand how there is not a proper system designed to work with variable speed heat pumps. Gah. So many beautiful products on the market and I can’t use any of them?!
I am going to look into Sensibo as well as Control4 but there is so much to consider and I don’t fully understand it all yet. So issue #1 is the variable speeds for heat pumps.
What other disadvantages come up trying using 3rd party controllers? I am trying to compile info so I can ask our installer and maybe the engineer as well.
Check EISY Polyglot interface from Universal Devices. I use the software to adjust setpoints for lighting and fan devices.
https://www.universal-devices.com/
Every brand has an interface to the antiquated multi wired universal interface with one wire for each function low heat, high heat low cool, high cool, fan and so on. Something like this photo is required.
Each brand has also developed a proprietary communicating interface with 3 or 4 simple wires to replace the rat’s nest but all the equipment must be from that brand and have the communicating feature.
Without some secret inside information hacking communicating system seems very unlikely.
Walta
For a sleek and easy-to-use control setup, I’d suggest checking out the Ecobee SmartThermostat. It has a great app and a modern interface that should suit your taste. I’ve used it with a similar HVAC system, and it worked pretty well. Another option to consider is the Honeywell Home T9, which also integrates nicely with different systems and has a decent app for managing things.
For your ERV, see if Van-ee offers any smart control options or look into a home hub like SmartThings. It can tie everything together and let you control both the ASHP and ERV from one place. I totally get wanting something that looks good and is easy to use—after all, who wants to deal with old-school tech if you don’t have to?
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Here is the the sequence of operation for the thermostat interface. The fans can run in auto and vary speed according to demand (see attached image). There are a couple dipswitches that change the behavior. https://mylinkdrive.com/viewPdf?srcUrl=http://s3.amazonaws.com/enter.mehvac.com/DAMRoot/Original/10006\Application_Note_3062_ME_-_Thermostat_Interface_2_Sequence_of_Operations.pdf
Install guide: Shows wiring to conventional old school stat (ie. Nest/Ecobee).
https://mylinkdrive.com/viewPdf?srcUrl=http://s3.amazonaws.com/enter.mehvac.com/DAMRoot/Original/10007\PAC-US445CN-1%20Installation%20Manual.pdf
Thanks, I am not smart enough to understand what this means.
I just looked into it a bit more, and it seems more complicated than just “variable speed” as the heat pump is VRF which I don’t fully understand. What is clear, however, is that Mitsu has propriety communication controls in order to get the full functionality and efficiency of the VRF. I don’t know why we even got this fancy heat pump, what a nightmare. I would really love to use something like an EcoBee, but it seems to defeat the purpose of such an expensive heat pump and we could have just gotten something much cheaper that could work with normal smart thermostats. The issue is also that I am not an engineer and would not be able to hack something myself, so it is up to the installer or our engineer and I don’t think they have a clue. The options seem to be get the horrendous Mitsu Kumo, or keep the archaic standard controller.
An update for anyone who might stumble across this post in search of the same answer…
My installer recommended Aidoo by AirZone which is compatible with VRF units. Unfortunately we still need the PAR40 t-stat but at least we can use an app with it.
https://www.airzonecontrol.com/na/en/control-solutions/aidoo/