Smart Thermostat

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Afternoon,

I currently have a Honeywell ST9400C programmer with a DT90E thermostat. The programmer is generally left to continuous with the thermostat used to control the heating being on/off.

I’m considering options to upgrade to a smart thermostat. Is there a smart thermostat that will work alongside the existing programmer? Or am I looking at a new system entirely?

Thanks,
Chris
 
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Any smart thermostat will do, just do away with the existing controller and thermostat, the smart stat will control everything
 
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What do you consider is a "Smart" thermostat? In the main they replace the programmer, and you don't have a wired thermostat, but it varies, Nest Gen 3 can have a wired thermostat although 12 volt, Nest e is heating only, neither connect to the TRV's.

Drayton Wiser the TRV is the clever device, both can use Opentherm, as can Honeywell Evo home, where the wall device is more like a hub.

Hive does not have OpenTherm as compared to others is rather low tec. Moes like Nest does not have links to TRV's EPH also does not link to TRV's but does link with a master/slave system, and uses motorised valves.

So there are many smart systems, so more down to selecting one that suits you.
 
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"Smart" tends to mean controllable remotely through an app. The DT90E can't do that.
 
Yes this was what I meant. I ideally wanted to leave the programmer in place (just for ease) but sounds like a case of replacing that too
 
Yes this was what I meant. I ideally wanted to leave the programmer in place (just for ease) but sounds like a case of replacing that too
Not strictly speaking, you can leave the other programmer in place, however, the “smart” thermostat may be programmable, which would mean setting the old one to always on.
 
Afternoon,

I currently have a Honeywell ST9400C programmer with a DT90E thermostat. The programmer is generally left to continuous with the thermostat used to control the heating being on/off.

I’m considering options to upgrade to a smart thermostat. Is there a smart thermostat that will work alongside the existing programmer? Or am I looking at a new system entirely?

Thanks,
Chris
Honeywell Lyric will give you all levels of smartness. Geofencing, OT if your boiler supports that and operation from near and far.
Honeywell Evohome takes it even further,
 
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I also find the word "Smart" confusing. I would personally say the device has some algorithms which work some thing out, to automatic give a better control?

So the Drayton Wiser TRV head is designed to work out how fast a room heats, so it can adjust the anti hysteresis software to ensure no over shoot, and at temperature at the set time, not just starting to heat at set time, and that I consider to be smart.

But the Hive wall thermostat has no algorithms built in, it is rather basic, only thing it has is telemetry, which is not really smart, think it may have geofencing as well, not sure?

Nest Gen 3 has all sorts built in, but with only one temperature sensor for European version, it is only any good for OpenPlan homes or hot air systems.

@Chris1784 seems to only want a thermostat, and has said nothing about linking TRV heads, so the Nest e is simple to install, battery powered, it does I seem to remember have OpenTherm but using simple on/off controls just two wires.

I think if I could run in new cables I would go for the Drayton Wiser as it seems to have the best TRV heads, but the Honeywell EvoHome allows one to set each room without using a phone to do it with, and I don't carry the mobile phone around in the house, however wife it tends to be stuck to her fingers.
 
I also find the word "Smart" confusing. I would personally say the device has some algorithms which work something out, to automatic give a better control?
I'm just trying to work out what the acronym for your system would be AWWSOAGBC?

Or...

Algorithms Which Work Something Out autoMATICly for Better Control.

AWWSOMATIC BC? ;)
 
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I like SCARDA and HMI's being able to control things from a distance, has always started with the "tele" prefix, telephone (voice at a distance) television (visual display at a distance, but there are always those who don't realise, so call it telefax rather than phonefax. Non distance fax was called a photostat.

So the word for control at a distance will likely start with "Tele" so likely Teletherm would describe using a thermostat at a distance.

But even words like "zone valves" these cover the thermostatic radiator valve (TRV) as much as a more traditional motorised valve, just spent the morning changing the batteries in mine so non leak and destroy the units.

But also the TRV is a thermostat, no argument about that, before the TRV it would be called either a room thermostat or simply a thermostat, now we need to call it a wall thermostat, and even that not so easy with cradles to allow thermostats to be placed on a table.

Nest calls the box of goodies the "heat link" the control module is called a "Display" and any extra measuring devices "Sensors" although not available yet in Europe only USA. The whole set-up is called the learning Thermostat, they don't call it "smart" they call it learning.

I never bother using my mobile phone (since used for written and picture massages maybe should use the star-track name the "Communicator") to set the temperature, I did use geofencing until it failed when EE mast damaged in wind, and I have read the temperature shown on the TRV head to decide if to turn on the AC. But in the main simple timed temperature changes are enough. And I have had a device for years that did that cost around £35 and called a programmable thermostat.

But this is an plumbing forum not English language well in the main new words come from a now disused language called Latin. Even plumbing is from the Latin, a worker of lead, if the guy can't wipe a joint, their not a plumber.
 
This is the current wiring set up. I guess if I chose to replace with either a hive or evohome (which seems a further step up in ‘smartness’) - it’s a relatively simple change for an electrician?
 

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Should be easy enough to do, doesn’t have to be an electrician, a decent heating engineer can do it.
 
This is the current wiring set up. I guess if I chose to replace with either a hive or evohome (which seems a further step up in ‘smartness’) - it’s a relatively simple change for an electrician?
Can anybody tell if this thermostat is low or high voltage from the picture alone?
 

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