Smart wired thermostats required

[mudmouse]

I have an underfloor heating system with individual room thermostats wired back to a central control unit.

I am looking to replace about 6 thermostats with hard-wired smart units that can be controlled remotely by my phone.

I am NOT looking for a cloud-based system as these rely on an uninterrupted internet signal. I live in the country and the internet regularly goes down.
Tado and other similar cloud-based systems are not suitable - if the internet goes down they do not control the system until the internet is restored and this could potentially allow the pipework to freeze even when set to frost mode.

Does anyone have any experience with any suitable thermostats which can be turned off holiday (frost) mode remotely by smartphone so I can come home to a warm house after a week away?

TIA

[ericmark]

Under floor heating does not respond fast, so geofencing will not work. The same applies for most telegraphy functions, so the question is what do you consider smart?

[mudmouse]

Hi Ericmark, I am not interested in geofencing just the ability to control the heating system from an android phone.
For reliability, due to flaky internet, I do not want a cloud-based system so that if the internet goes down the unit has a stored program.
I am looking for reliability with the ability to remotely control the heating.

[Someone-Else]

mudmouse, only asking. You said you have 6 stats that are all wired to a "central control unit"
Question. What will this central control unit accept?

[mudmouse]

SE I have about 14 stats in total but only need to controll 6 of them. They are hard wired back to underfloor heating controller boxes which turn on the zones via 2 manifolds. All I need to do is send a signal back on each of the zones when heating is required in that zone. I have dumb programable thermostats at present but would like to have the option to remotely adjust them via a smartphone.

[Someone-Else]

So you are saying it must have clean contacts only?

[mudmouse]

They switch a 230v signal. NO when off.

[Someone-Else]

I have been looking (TBH I am just curious) I have come to the conclusion that if you do not want it cloud or internet based it can be done but at a cost, a large cost.
I have found These. click here These work on zigbee (worry about that in a minute) but they are £50 each, and as need 6 of them that is £300 before you start. It's not my money, but if you want to go ahead.............

I can't help but wonder, would it be possible to buy one of the stats, and connect it to your "central control point" (I genuinely do not know)

As for zigbee, it is a radio protocol that a lot of devices use (Even philips hue lamps use it) The idea is you get a zigbee hub or as I have (still working with it, so not all set up) a Hubitat

h.jpg (8.05 KiB) Viewed 467 times

(Above is my hubitat)

As it uses zigbee, if the internet goes down, it, and anything connected to it still work, yes it uses the internet, but you can use your phone and the internet if you are not at home, and if the internet does go down, as I said, anything at your home will still work because it is running on zigbee, the internet is only used to check in, or change things (You can also do this from a computer or tablet)

A hubitat is not cheap, Click here but it can operate loads of devices (I am still learning) But one other advantage, a lot of "Technology" companies are going bust, so if you have their stuff, it will soon stop working, even if hubitat went under, it uses zigbee, and it works with no internet.

Overall, (As I said) It's not my money, but it can be done, but not cheap.

I honestly hope that someone else (I do love my user name) on this forum can come up with a better idea, but so far...........

[mudmouse]

SE thanks for input, it has been a great help (and a time-consuming educational distraction).

As a bit of background, just before Christmas I installed a number of wired Tado thermostats, primarily because they were available at Toolstation, which is just down the road from me. I started out in blissful ignorance of what is available but just tried the Tado as it seemed on face value to be a reliable system for my rather limited (up to this point) need to control my heating system when I am away.

On using the Tado system it became apparent that it relies totally on a 100% reliable internet.
We live in the country where the internet can be quite unreliable. It was at this point I realised that should my internet go down that I would then have a completely dumb heating system that would either keep the heating on, come what may, or leave it off whatever the temperature inside or out – they do not tell you this anywhere and most users are probably unaware of this limitation, at least until they have an internet outage.

The way the Tado system works, which you are probably aware of, is that the thermostat is not in actual fact a thermostat since it cannot on its own control temperature. It does so by having an internal thermometer that sends a signal back to the Tado servers which then sends a signal back to the unit which has a switch controlled by the servers at Tado. Should the internet go down the unit then stays in the same set condition (fully on or off) until the internet is restored and the servers can signal to the switch what to do.

My initial view after taking out every Tado thermostat and sending them back for a refund was to research the issue a little more.

It was at this point that I came up with the Salus Quantum system which like your Hubitat utilises Zigbee, the only problem with the Salus system is that it does not talk with anything other than the Salus hub, and whilst smart, is not as easily programmable as lots of other devices.

My dilemma is whether to continue down the Salus route or pick another system that allows other manufacturers' products to work on the same hub like the Hubitat. The only problem with this is the potential problem for others down the line should I sell the house, would they understand it?

A couple of years ago I started developing a Raspberry Pi control system for the entire heating system. I got to the point where I could measure temperatures around the house and throughout the heating system (which is already complex as I built the house to my specification). I did not take it any further due to SWMBO saying that neither she nor any plumber would be able to sort out any problem due to its complexity. This would also be a concern should I go for a hybrid approach using different manufacturers' components and bespoke software (I love Python but not many plumbers do!).

So this is now my dilemma – buy the Salus Quantum or go with a hybrid but probably more flexible system – What do you think?????

[ericmark]

I slowly progressed, at first mother house, heating was a mess, and we ended up with energenie mihome TRV's, light switches, and socket, mainly for the socket which powered the extruder alarm for when my mother escaped. At her house they worked well, and the instructions said they worked with Nest, they needed a hub to set them, but once set would continue to work, and the switches and sockets would also work with a remote control.

We moved here with all my mothers stuff, new owners did not want it, so removed and standard stuff put back, central heating here was a mess, so since Nest was claimed to work with energenie TRV heads we fitted Nest, it did not work with the TRV heads, and the Nest thermostat was very disappointing.

We also found FM radio does not work here, so got Nest Mini to listen to music, and for that they worked well, since energenie had worked well, we got more, but then the troubles started, 3 or of 5 switches now decommissioned, and one socket.

Next was Lidi stuff, they used zigbee, we had to get hub elsewhere around £15 from memory, but got bulbs, sockets, relays, since then also used TCP and 4lite wiz bulbs, yes I know your looking at central heating, but they all interconnect. The Moes thermostat I think is zigbee and about the cheapest there is, around three models, and I know one is designed for under floor heating.

Although the Nest Mini has worked well, some times it is like a mischievous little boy, as it to turn off landing light, and it says turning off 5 switches and you wonder what else has it turned off. I have never trusted it with central heating, but it will work it if I want.

The problem I have is the central heating is slow to respond, so if it stops working, it can be a few hours before I realise, this time last year we had high winds, which took out the EE mast, so central heating thought I was not home, and went into Eco mode, but each time I walked past the thermostat the built in PIR detected me, and turned it up to comfort, result was it was about 36 hours before we realised why we were so cold. Easy enough to switch the function off once I realised the problem, but automation does have draw backs.

The problem with UFH is speed of response, so not sure automating it will help, heating does work without internet, but wifi linked thermostats start at around £55.