I know this has been asked on multiple threads, but after reading through many of them I'm still undecided and a bit confused.
I'm looking to buy smart thermostats.
I may not have the terminology correct... but I believe that I have a 2 zone system. One HVAC unit with a small system in the attic that splits the system into 2 zones... upstairs and downstairs, controlled by two separate thermostats. Based on the wiring, I believe that it is just a 1 stage system with emergency heat, which is only wired in the downstairs thermostat with a jumper wire. That jumper wire doesn't exist in the upstairs thermostat wiring.
I'm looking to buy something that I can control through Alexa Voice commands, motion sensors controlling the temperature based on which room I'm using, and of course presence, and possibly humidity through sensors if possible. I'm assuming that I can achieve those things with any smart thermostat connected through the Hubitat along with a few motion sensors.
I tend to lean towards Z-Wave devices but I haven't ruled out Zigbee all together.
I'm kind of leaning towards the Go Control Z-Wave thermostat. I like that it's Z-Wave, will have local control through the Hubitat and the price doesn't hurt either. It's not the prettiest looking thermostat out there, but if the functionality is right, I can overlook the looks. The Zen and KONOz are also on my radar. Although, the KONOz seems to be out of stock and I'm a bit confused if the Zen will actually work with my system or not.
Additionally, I haven't completely ruled out something like an Ecobee or Nest, but I'm not sure that makes sense when I have a Hubitat.
Any input, pros/ cons, or other suggestions would be greatly appreciated.
Different people have different definitions for what makes a thermostat "smart". To some people, that means being able to adjust it from a phone app or with Alexa, Nest has the philosophy that the thermostat should have built in "intelligence" that allows it to infer what the setpoint should be without the user having to enter the setpoint and/or a schedule. For others, it means being able to communicate with a hub like Hubitat which provides an opportunity for the homeowner to take advantage of all of the information from other sensors throughout the house to improve HVAC control. In that last category, the thermostat itself doesn't contribute the "smarts" but plays nicely in a "smart" system. The Zen thermostat, for example, has no scheduling capability by itself, but integrates nicely into a home automation system that can schedule setpoints using very sophisticated logic.
Your terminology is correct. You probably have a board called a zone controller near your air handler that receives the signals from the two thermostats and decides what commands to send to the air handler and to zone dampers. The common way to add smarts to such a system is to swap the thermostats for smart thermostats, using whatever definition you prefer, and let your zone controller continue to function as it does now. I have written a Hubitat app that replaces the zone controller itself. However, as noted below, I don't recommend that for you.
The fact that you mention emergency heat leads me to believe that your system is a heat pump system. My Hubitat zone control app does not yet support heat pump systems, although that is on my list of future enhancements. A lot of 2-stage systems get wired as 1-stage systems with the air handler itself deciding when to use 2nd stage. The usual logic is for it to go to 2nd stage after running for 10-12 minutes in 1st stage. That distinction doesn't really impact your thermostat choice.
With these goals, I recommend avoiding any thermostat that tries to put a lot of smarts in the thermostat product itself. Having the thermostat and Hubitat both trying to be in control is sort of like having two people both wanting to be in control. ZWave and Zigbee devices tend to fit better into a Hubitat system than devices which require cloud integrations, like Nest or Ecobee.
That would be a good choice.
I bought a Zen to test. My wife liked the aesthetics of it, so we ended up leaving it in place after the test and getting another one for a different zone. Setting up the Zen was a little more challenging than the other models I tested, but I'm pretty sure you will be able to set it up for your system.
It sounds like my intuition with the the Go Control probably being my best option was right. I do Like the design of the Zen, but it costs a lot more than the Go Control... and buying two units adds up! Can I ask what was challenging about the setup with the Zen?
I don't want to make it seem like a bigger deal than it is. The combination of a thermostat that is capable of handling a wide variety of types of HVAC systems and also has a user interface with very few switches and buttons, configuration is likely to take a lot of button presses. I had to find instructions for configuration on the internet. (I bought mine refurbished. Maybe it is in the package for new units.) Configuration required taking the thermostat off the wall plate and pushing configuration buttons on the back to set the type of system. I wouldn't consider this a reason not to buy the Zen if it otherwise meets your needs.
I don't have personal experience with the Honeywell T6, but I have heard good things from others. I think you would be happy with that if you go that way.
well, I ordered two GoControl thermostats and they came today. I made the mistake of trying to switch them out tonight. I couldn't find a breaker for the HVAC system to shut off the power. I tried everything I could think in the box that could be powering it. No luck.
I figured it was just low voltage wires... what could go wrong. So I decided to go forward and wire everything up to the new go Control unit downstairs.
When I had everything together... the power wouldn't come on on the unit. I checked my upstairs thermostat which was still the old one... no power there either. So... I went into the attic to see if there was a fuse or breaker up there. The breaker up there, attached to the blower unit, wasn't tripped. The only thing that I could find was the box where all of the low voltage wires were distributed. It looked like that low voltage box also had no power. There looks to be some LED's on it and none of those LED's were lit.
So, I climb out of the attic and decided that maybe I just wired it up wrong. I rewired my old unit the way it was and threw it back on the wall... still, no power upstairs or downstairs.
So essentially, I think I broke my HVAC unit! I'm hoping that it's just a fuse or breaker someplace.
Any help or suggestions would be greatly appreciated before I have to call HVAC maintenance tomorrow.
Ugh, that's a nightmare... potentially expensive and bad for the WAF. A few things to look at. First, in your main electrical panel, the heat pump unit is probably on a 50 amp double breaker. The only other double breaker you should have which is that highly rated is for your range, if it is electric or an electric dryer if it is 220V. Breakers can sometimes trip but not throw all the way to the off position; you have to manually flip them all the way to off and then back on to reset them. Second, if you have a multimeter, take a reading of AC voltage between the C and R wires. If it does not read 24V, you have no power to the unit at all, which points to a tripped breaker somewhere.
Yeah... it’s not easy to get up to the attic where the blower unit is, which is why I didn’t go up there before trying to switch out the thermostats to check what’s going on up there. If I did, I probably would have switched off the breaker up there running to the blower unit. When I checked it, it looked fully on... maybe it wasn’t. I’ll climb back up tomorrow and flip it back and forth to reset it.
I don’t have a multimeter, but I may go pick one up tomorrow to test things. I need to get this fixed ASAP so that I have heat. I’m in Tennessee, so daytime isn’t bad, but it does get cold at night. Luckily, I have a few space heaters.
From everything I read, this didn’t seem like a bad DIY project. If I thought I couldn’t do it, or would screw something up, I wouldn’t have attempted it. I guess you learn the hard way. I’m a fairly new home owner, so I keep learning new things as I go. So far, I haven’t screwed anything up. Hopefully this isn’t the first major blunder for me.
I’m hoping there is a breaker flip or a fuse to replace and everything will run again.
I can tell you where the breaker is on my system, but no guarantee yours is the same. (I have tripped it trying to change wiring with the system on.) My furnace is in the basement, so the ergonomics of working on it are much better than in an attic. There is a switch on the side of the furnace that turns the 120VAC on and off. That is the easiest place to turn the power off to do wiring changes, but it is not a circuit breaker. It is just a switch, at least on mine. Inside the blower cabinet, there is a transformer that creates the 24VAC. There is a circuit breaker on that transformer, which is what tripped when I screwed up wiring mine. Power does not immediately come back on when you reset that circuit breaker. You have to put the cover back on the blower cabinet. There is some sort of switch that automatically turns things off when the blower cabinet door is removed. Hope that helps.
Don't be too afraid to call an HVAC company if you cannot figure it out and don't have a friend or neighbor that is knowledgeable. I called an electrician for help once when I screwed up installing a smart switch. The electrician was able to tell me over the phone what to check for, which turned out to be the problem.
I watched and read a bunch of stuff about HVAC systems last night. So I have a better idea what to look for when I climb up there today. I’m not sure I know how to get into the blower unit. I don’t remember seeing an obvious way to get into it, but I’ll look around once I’m up there. I do have a separate breaker up there. I would have never guessed that there was one up there! No switch, outside of that breaker, that I saw though.
I figured it out!!! The fuse was shot! So I shorted it out when messing with the wires. Now I know better! Thanks for all of your help! I'm glad that it wasn't a bigger problem.
One final question... The Fuse in the blower had "E" marked on it and was purple. I replaced it with what I had... a similar looking 3amp car fuse. Do you know what amperage "E" fuses are? And, should I replace it with the proper furnace fuse type? I checked online and at home depot and can't seem to find "E" fuses.
thanks again! now to get these new thermostats paired!