Zoned Thermostats with Central Interface - What works well?

[jk96]

Title basically says what I'm after. I've got 6 zones total including the basement and am looking for an integrated system with central controller and phone app as well if available. My schedule is not set and varies so using a programmed t-stat for the zones doesn't always work well. I'd like some type of central interface for all of the zones to be able to easily adjust, turn off, on, etc without having to physically walk to each t-stat in the house. I ran across honeywell's evohome system but it looks like it's for the UK only and for a boiler/radiator system. Anyone have suggestions?

 

[Paddy]

What is your heating system? We have radiant with many zones, but rarely touch them.

 

[jk96]

What is your heating system? We have radiant with many zones, but rarely touch them.

We have geothermal water to air. Wish I would have found the money somewhere for radiant. I know with geo its normally set it and forget it however in our situation the combination of an oversized system, very tight house, & closed cell spray foam makes for very fast recovery. The 1st floor main living area is open to the 2nd. When I'm gone I usually only leave the main zone running and kick the others back on when the kids and wife are home from school and work.

 

[s219]

We have a Honeywell controller running our geo system, which has two zones, duct dampers, and a multi-speed fan, all used to handle different combinations of zones calling for attention. I believe that controller can handle up to 4 zones, and they may make bigger controllers. Don't know about phone/app interface but I recall that interface hardware can be added that would enable outside control. I can say I am impressed with the capability of the controller during the few times I had to troubleshoot something, especially considering I figure out HVAC by the seat of my pants.

 

[Paddy]

jk96,

I don't know much about Geothermal. But with heat pumps, if the set temp is above the room temp by too mush, ele strips cut in until the difference is small. This helps for fast recovery. If that is the case with your system, you could be enjoying a COP of 5-6 by one set temp. But if a room is allowed to chill by 3 deg by T-stat, COP of 1 may be the price to get it back up to temp. I suppose you could trick it; have it climb in 2 deg increments over a 1/2 hr.

I have guest bedrooms with T-stats fully off. Rooms are insulated on all 4 walls to keep side spaces from residual heat lose.

I like the idea of more control.

 

[teejk]

We have 6 zones on a boiler fired radiant system. My heating guy is a "commercial" contractor so I have each zone on a separate pump, thermostat and Honeywell relay. I asked him about the cost of a central control and he just laughed...very pricey! Our zones are basement, master/vanity bath, master bedroom, living space and 2 upstairs bedrooms. Once balanced to our comfort we never touched the thermostats on floor 1. Upstairs bedrooms...when we get guests we'll let them use their thermostats (we installed a "suspended" radiant system on a "tight" house...doesn't take long to bring the temp up).

 

[jk96]

Paddy we do have backup heat strips but they are on individual breakers. I've got them off so that even if the tstat calls they wont come on. We have never needed them even with temps into negative territory.

I did some more checking and it looks like I could go with honeywell wifi tstats and control from their total connect app but that gets pretty pricey with 6 tstats. I'll have to find out if their cheapest wifi tstats are compatible.

 

[buckeyefarmer]

I use Honeywell IP linked thermostat's for my 2 geo systems. I zoned mine with an upstairs unit and downstairs unit. nice to control them with my phone.

 

[yankeerider]

Look into Z-wave thermostats to replace each of your individual ones. You'll also need a hub to act as the central controller. I cannot speak from experience for heating control, but I have recently set up a Samsung Smartthings hub that talks to three separate GE z-wave light switches. It allows me to turn lights on or off locally or from my smartphone over the internet and program automatic switching based on a variety of factors. The hub cost $100 and the light switches were about $38 each. Z-wave thermostats look to be in the $100-$200 each range.

Here's a link that might help you get started looking:
What is the best Z-Wave Thermostat 2016? - Reviews

Also read reviews on Amazon

 

[s219]

Our Honeywell controller allows us to choose 3-4 different behaviors for the electric strip heaters -- time based, temperature differential based, thermostat based, and a couple others that I can't remember.

One important reason to allow use of strip heaters with a geo system is to prevent the ground loop from chilling down too far in situations where the geo system requires very long run times to reach target temps in super cold weather. I believe it's in your interest to mix in a little strip heat in those situations (some people have backup propane/gas heat for those scenarios, which would be much more efficient than strip heaters).

Like everything, there is an optimum. All depends on the climate and many other factors, including how you set your thermostats. If you set the system to a much lower overnight temperature, the morning ramp up to a warmer temperature could result in long run times and cause efficiency to drop off as the ground loop cools.

We had our strip heaters turned off the first couple years due to a programming error. Got them activated middle of last winter and they've been available all of this winter. Have not really noticed if they are used a lot, and haven't yet seen any impact on the power bill. But I sure knew something was wrong last winter when we had a super cold snap and the geo loop temp dropped dramatically due to long run times.