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Review of new Honeywell TH8320ZW programmable thermostat

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3.8K views 5 replies 4 participants last post by  Paul Scobie  
#1 · (Edited)
Today I replaced the programmable thermostat on our electric furnace with a new model that can be remotely controlled. I thought i would post some pictures and give some impressions of what I got in case anyone would be interested.

I ordered the thermostat from the Home Depot website and it shipped out in a week. The box that came was marked YTH8320ZW1007. This contained the thermostat and the THP9045 "4 wire to 5 wire converter" which I was not expecting (no mention of it being included on the website description) I did not use the converter but it is nice to have should I ever need it in the future. (the converter is used at the furnace side the thermostat supports it natively)

The furnace I'm using this with is an old Lennox electric furnace probably dating from when the house was built in 1973. I am sure when it was installed there were only 2 wires coming from it (the R and W wires) to the original thermostat which was one of those round Honeywell bimetallic strip mercury thermostats. (paint marks on the wall definitely show it was one of those) But at some point probably back before 2006 (when the basement was remodeled) they ran a new thermostat wire that contained 4 wires, the Red Blue White Yellow wires and then they did a little rewiring at the furnace to extend the common (C) wire. For some reason they connected this to the Yellow wire instead of the Blue wire. So I had the Red Yellow White wires live at the thermostat with the C terminal being on Yellow.

I turned off the breaker and took the furnace panels off to figure out the wiring since I did not trust the wire connections at the existing thermostat.

After reading the installation manual and figuring out what was going to what I connected and mounted the thermostat and turned back on the furnace to make sure the thermostat would power up from the transformer in the furnace, then I pulled the packing tab out from the battery in the thermostat and we are off and running.

Another thing I liked about this thermostat was it was tall enough to completely cover the junction box on the wall that the original thermostat used.

The thermostat uses a coin Lithium battery to save the programming and clock and temperature settings. It does not draw power from this unless the AC power fails.

I'm going to be rigging up the Zwave tomorrow and I'll follow this post up with the results of that.
 

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#4 ·
How about keeping track of just how often you use the remote feature in a year?
And what those circumstances might ever be...
No need to keep track. I use mine multiple times per day. Far more than I ever expected to.

First thing, turn down the thermostat so the heat doesn't come on while I'm working out. Can't set a schedule for that since I'm not on one.

Went to bed early? Turn down the living room zone earlier than the schedule would normally turn it down.

Got up early? Turn down the bedroom zone once we're settled in downstairs.

Going out for a while? Turn down the stats. Coming back? Turn them back up.

In summer, there's only one air conditioning zone, so that one probably only gets used once or twice every day or two.

I rarely use the thermostat directly. My phone is with me all the time. Even if I'm home, it's quicker to launch the app than walk over to the stat, push a button to bring up the backlight, push another button to cancel whatever button I'd pushed first, then try to do what I want before the backlight times out again. Plus the app shows me all three stats, plus outside temp.

I really was skeptical that I'd ever use the remote feature much. I only got it because we were going on a trip. But now I can't imagine not having access to my thermostats from wherever I am, be it sitting in my easy chair, or a thousand miles away.
 
#3 ·
Well, the house is a second home for us - it's a vacation home on the coast that's about 2 hours away. We also want to rent it out on occasion to vacation renters. Normally the house is kept at 55 degrees when nobody is there. I don't want to lock out the thermostat from the renters changing the temperature but I definitely want to make sure that when the rental period is over that the thermostat is reset back to 55 degrees and I don't want to depend on the rental management company's cleaning staff to do this. And of course it would be nice to boost it to 70 an hour or so before the renters arrive.

The house also (unfortunately) has one of those Vermont Castings "Radiance" natural gas fired standalone fireplaces with a millivolt gas valve in it. I don't want renters turning the thing on and then forgetting about it. The model I have also does not appear to have a thermostat so it will go on and just stay on forever and heat the house up to God-knows-what. Warming the house in advance should help to curtail the desire to turn on the fireplace.

The thing is though that with this home automation stuff that the cat's meow is to setup a geolocation program on my wife and my smart phone - so that when we get within, say, 30 miles of the house that the thermostat is automatically turned on and when we get within a mile of the house all the house lights go on, and so forth. But it takes a while to replace light switches with the Z-wave light switches particularly when the house is filled with those nasty little 3x2x 1 1/2 junction boxes. And of course you have to configure them.
 
#5 ·
This is the second part of this review.

The thermostat is configured out of the box with a temperature setting of 70 degrees and no programming. The first thing the thermostat requires you to do is set the time and date and clock using the touchscreen. The touchscreen is also used to set the Mon-Sun temperature schedule. However, the point of a Z-wave thermostat is not to be controlled by a schedule set into the thermostat but instead be controlled by the home automation hub so I did not set a program into it.

In my case since this was just an electric furnace that didn't even provide a "fan only" wire to the thermostat, I had to set the thermostat to "Heat" instead of "Auto"

After verifying that the thermostat worked as a thermostat, I installed the VeraPlus Advanced Smart Home Controller. I bought this as part of a "security kit" which means that besides the box containing the Vera controller it also had a battery operated motion detector, a battery operated door sensor and an A.C. powered Sounder/Alarm. Those were an extra $50 with the package and I thought I would give them a try. The entire package was on sale off the Vera website.

I ran into a few glitches when setting up the controller. First thing was it would not completely power up and obtain an IP address via DHCP. That was fixed by doing a factory reset to the controller with a paperclip (press the reset button 6 times in a row, quickly, and wait a minute and the controller resets.) Then once it was powered up and on the network the Vera servers did not say that the controller was online. But the servers did refer me to the internal IP address of the controller and it allowed me to configure it by accessing it's IP address directly. Then the last thing was once I got it configured and the Vera servers did show it as online, i was not able to access it remotely using the Vera servers. I had to call Vera tech support who had me enable the Support SSH server so they could remotely login to the controller, and when they did that they told me that they had to do a firmware update to the controller, which was interesting because the Vera webinterface said that it was at the current firmware.

I was impressed with the Vera tech support, I called in at 11pm on a Saturday evening and got a tech online within about 3 minutes and they had the problem solved within a half hour and called me back so I didn't have to sit on hold the entire time.

I installed the Vera Plus in the garage on the first floor. Pairing the Thermostat with the Vera was a snap. Just go into Add Devices, select a Generic Z-wave device then set the thermostat to pairing and the Vera will connect. Pairing the motion sensor included in the kit was a huge amount of trouble, however. I had to reset it several times and it was difficult to open and close to get the battery in and out. I'm also not particularly excited about a motion sensor that doesn't require power but instead uses a battery but that's what cheap buys you. The kit also includes a siren strobe sounder powered by an adapter and that is worth it since because it's powered it is also a Z-wave repeater. I have that on the second floor so any future motion sensors I add there should have no issues. I will probably get one of the multipurpose temp/humidity/motion/light sensors for the second floor.

I strongly recommend the VeraPlus controller. Unlike many other home controllers it DOES NOT require a constant connection to the Vera cloud servers. In fact if the Vera servers were to disappear tomorrow the VeraPlus controller would still be useful. Or if the Vera company decides 10 years from now that the VeraPlus is old technology and they aren't going to support it any longer, you will still be able to use it. And the VeraPlus supports 2 methods of remote access. First it can use the traditional "port forward" method just set a static IP in the controller and do a port forward in your router to port 80. This assumes your using dynamic DNS on your router. Second, when the controller is booted it logs into the Vera servers on the Internet in the cloud, and you can access those servers with a web browser and thus access the thermostat.

The home controller has very flexible programming and it uses an event driven setup. For example you can set the temperature to go up at a specific time and/or day and you can set it to go down at a specific time and/or day. You can set it to go up if your smartphone is within 2 miles of the house with "geofencing" if you install the Vera app on your smartphone. You can set it to go up if for example you have a keypad lock on the door and someone enters the keypad and unlocks the door. You can even set it to turn the furnace on if the outside temperature drops below a certain level, if you pull temperature from wunderground.com

I know it seems like i have wandered far afield from HVAC into home automation but the fact is that pairing a Z-wave thermostat with a home hub controller is a superior way of getting a remotely accessible thermostat than buying the off the shelf wireless thermostats which are only compatible with their manufacturers cloud offerings. And it isn't really that much more expensive.