Thermostats - looking for some suggestions

[KenN]

Hey all,

Now that I've got the Elk/Insteon install well on its way (we all know it's never actually done, there's always another thing to do, idea to test ...), I'm looking to bring my thermostats into the fold. My research so far yields results for various thermostats that are enabled with any number of the usual HA communication method. But, since they aren't exactly cheap, I'd like some input before running out and buying ... so, what I have now;

- House is heated with in-floor hydronic radiant heating. There are six zones, two on each of three floors.
- Each zone is controlled independently by a dead simple thermostat - just the basic pointer that moves to the temp setting, bi-metal switch inside opens/closes a contact to actuate a solenoid that allows the hot water to flow (simple, typical stuff)
- Two conductor wire only to each thermostat, 24 VAC fed along one conductor, contact closes, the other conductor goes to the solenoid, solenoid connected to the other leg of the 24VAC xfmr to complete the circuit.
- There is no central AC or AC of any kind. In Vancouver, we have 1-2 weeks per year that get hot enough where AC would be nice. Not nearly enough to justify the thousands it would cost to put all the ducting and wiring needed for cooling control! Fans do the job nicely.

So ... I'm finding lots of full-function thermostats that do heating, cooling, multi-day scheduling, cook your breakfast and call your wife on your anniversary. I really don't need/want all this and these thermostats run about $150 and up. By the time I've paid tax and shipping on six units I'm looking at a grand to do the house! Seems excessive when all I want to do is set thermostats via automation protocol/programming and view temperature at each zone.

Any suggestions for a much less pricey thermostat that just does the basics? As I said, I'm set up with Insteon for now. I have some interest in adding Z-wave to the system (once UD releases their z-wave module for the ISY) so would consider that as well. The zigbee thermostats I found were super expensive, like $260 and up, so that's off my list.


Thanks in advance,
ken.

 

[JoshFerg]

Automated tstats are pricey, usually around $300 a piece.

In your case since you just have heat you could put temp sensors in the rooms and control the heat with relays. You would use the automation controller for all the logic.

Thermostats in each room is a cleaner/simpler approach, but this would save you some money.

Another option is 1 automated thermostat on your main zone. That may be enough to heat most of your home before you arrive, then kick the others on manually when you get there.

 

[tmbrown97]

I think in this case I'd agree; I'd consider getting the necessary relay outputs (M1RB or XOVR depending on what you've used up so far) and run that to the thermostats. If running wire is a possibility, I'd probably do it using relays in-line with the existing thermostats so that in failover mode, they work still. The trick is getting temperature into the system; if you can run temp sensors, you can wire in 6 of Elk's to the main board - may require some juggling of zones because they have to be on the primary 16 zones; or you if Insteon has a temperature sensor, you can use that to populate custom values via the ISY.

Just some options...

 

[KenN]

Thanks for the feedback ... actually, just this past Friday I found/ordered some 2gig CT100 thermostats. There was a good sale price at $85 each, so I ordered four. I figure this will cover most of my zones and I'll get something more sophisticated to install in our main living area, maybe something that can act as a thermostat, bring in outside temp and weather reports? Just thinking ahead.

These are pretty simple devices, no multi-day programming or anything like that, but they have integrated z-wave. Which, of course, means expanding my Insteon based HA system to include z-wave. But that's half the fun, isn't it?

I'm waiting patiently for UD to release the much-anticipated z-wave support for the ISY994 now!

I did, quite seriously, look into building a custom solution, lots of research to figure out just how to put it all into a nice looking box to mount on the wall - got to look professional. But when I stumbled onto the CT100's the economics pretty much favoured going that route.


brb, reading z-wave documents!

 

[BraveSirRobbin]

Thanks for the feedback ... actually, just this past Friday I found/ordered some 2gig CT100 thermostats. There was a good sale price at $85 each, so I ordered four. I figure this will cover most of my zones and I'll get something more sophisticated to install in our main living area, maybe something that can act as a thermostat, bring in outside temp and weather reports? Just thinking ahead.

These are pretty simple devices, no multi-day programming or anything like that, but they have integrated z-wave. Which, of course, means expanding my Insteon based HA system to include z-wave. But that's half the fun, isn't it?

I'm waiting patiently for UD to release the much-anticipated z-wave support for the ISY994 now!

I did, quite seriously, look into building a custom solution, lots of research to figure out just how to put it all into a nice looking box to mount on the wall - got to look professional. But when I stumbled onto the CT100's the economics pretty much favoured going that route.


brb, reading z-wave documents!

Doesn't that require subscribing to a service for remote access though?

 

[KenN]

Assuming you're referring to the thermostat (and not the ISY z-wave module)? Not from what I've seen, though I've been wrong before. The CT-100 appears to be a pretty new product, I had to do a few searches to find all three related documents (spec sheet, user guide and operations guide). These aren't even available for download from 2gig's own site!

Found the spec sheet and the user/operations guide at the Homeseer site --> http://store.homeseer.com/store/2GIG-CT100-Z-Wave-Programmable-Thermostat-P1324.aspx

Had to dig deep to find the installation guide --> http://cache.smithmonitoring.com/manuals/2GIG-CT100%20-%20Installation%20Guide%20-%20Radio%20Thermostat.pdf

Nothing seems to indicate the need for an account for remote connection. I do think I'll have to pull in new wire though as the existing stats use only 2-wire cable. I'll want a third wire per stat for full-time power so the communications mesh is solid, plus the third switched conductor to run the heating system solenoids.

 

[tomas21]

Check out the Nest

 

[tmbrown97]

Check out the Nest

And be sure to check out the reviews for the Nest too :blink:

And 6x$250 sounds to be more than he planned to spend.

 

[KenN]

And 6x$250 sounds to be more than he planned to spend.

Yip, that's kind of moving in the wrong direction!

But I am starting to plan for down the road ... rather than try to find a full featured stat for one location, I'm starting to think that I'll get the cheapie for all 6 zones. Then plan for a tablet running something like homeseer or elve for the central location. That way there will be place to bring it all together and put up pretty pictures. I think that's a better place to spend the $$$