Remote (SIM) control of central heating

Nest Labs brings ‘intelligent’ thermostat to Irish market

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Thermostat: €219 inc VAT
Nest is giving everyone who buys a thermostat between September 18th -24th free installation (normally costs €120)

http://www.irishtimes.com/business/...elligent-thermostat-to-irish-market-1.1932209

I wonder how this works if you need zoned thermostats i.e. one for upstairs circuit and one for downstairs circuit?

Will they install 2x stats? Will only one nest unit be needed?
 
Answering my own query - it looks like if you have zoned heating, then it's 1 nest thermostat per unit. Not as cost effective as I'd like (and very expensive for those of you with multiple zones) but it seems like a good system otherwise so going to go for it.



(ps. they don't accept visa debit card!)
 
Finally got around to unwrapping my "GSM Activate" switch and buying a Tesco mobile SIM card. I tested it standalone, and it does exactly what it says on the tin. Looks like simplicity itself. Here's some of the text messages I've been sending it (commands in green, responses in grey), but I have shortcuts set up so I can just type hxo, hxf, hxt, hxs for heating on, off, 18-hr timer, status:

Hy2iBj0.png



The last fly in the ointment is that, in classic Irish style, no electrician has got back to me about installing it ... probably too small a job, too far away.

So I'm going to illegally wire it myself ... like this:

znA12Be.png


The switch on the left is the existing "big red switch". The new DPDT switch (which I will label "GSM off/on") will let me short-circuit the GSM switch as if it wasn't there. When it's on, the system will then only come on and off in response to GSM commands. Looks easy enough. If nothing else I've learned a few new words of electrician-speak. I will post about my success if I am not fried in my attempts. :D
 
Remind me again Dub what degree of control you are seeking to obtain with the GSM R/C switch.

I'm just trying to work out why you need the "extra" DP switch.
 
Remind me again Dub what degree of control you are seeking to obtain with the GSM R/C switch.

I'm just trying to work out why you need the "extra" DP switch.

I literally just want to be able to switch the whole thing on and off. The reason for the second switch is that otherwise the heating can't be switched on without the GSM Switch being activated. The GSM Switch has no buttons or external controls for manual switching. What if I lose my phone or there is no cell coverage while I am in the house? -- I wouldn't be able to turn the heating on or off. So I need to be able to switch to "manual operation". (I'd love if I didn't need the second switch -- having quite some trouble sourcing a normal looking DPDT switch for mains voltage online ... any suggestions?).
 
I literally just want to be able to switch the whole thing on and off. The reason for the second switch is that otherwise the heating can't be switched on without the GSM Switch being activated. The GSM Switch has no buttons or external controls for manual switching. What if I lose my phone or there is no cell coverage while I am in the house? -- I wouldn't be able to turn the heating on or off. So I need to be able to switch to "manual operation". (I'd love if I didn't need the second switch -- having quite some trouble sourcing a normal looking DPDT switch for mains voltage online ... any suggestions?).


What's wrong with "the big red switch" for on/off when you're in the house?

Basically all the DPDT switch is doing is overiding the R/C switch, so you will have to remember to switch it out everytime you are going out and you want R/C of the heating. I fully understand where you are coming from re. no phone coverage, but that surely defeats the purpose of the GSM switch.

Just wire it so that the common and normally closed are in circuit so when it is off (at rest) the heat will be on, and should the GSM switch fail, and I'm assuming it will reset or return to default if it does, then at least you will have heat.

Also a single pole 2 way (change over) switch would do you, if you really want to be able overide the GSM switch, just run the live to the GSM switch and loop out to your SP (L1) switch and from that (common) out to your heat and , hey presto, manual overide.
I just feel that having to remember to switch it to "remote" when you go out somehow defeats the purpose of having the R/C option in the first place.

See my CRAP drawing, :) I didn't bother signing up, rushing, so its in some album or other.

http://imgur.com/a/r6rT9


PS. Just going out the door...........Even a single one way SW would do you, just put it across the common and the normally open of the GSM and mark it "MAN/REMOTE".
 
I'll try and address in logical order.... P.S. don't underestimate my cluelessness when it comes to electrics. :)

should the GSM switch fail ... I'm assuming it will reset or return to default if it does, then at least you will have heat.

Yes. I tested that. It has to be powered to connect the CO and NO. If it is powered down it reverts to connecting CO and NC.

What's wrong with "the big red switch" for on/off when you're in the house?

Basically all the DPDT switch is doing is overiding the R/C switch, so you will have to remember to switch it out everytime you are going out and you want R/C of the heating. I fully understand where you are coming from re. no phone coverage, but that surely defeats the purpose of the GSM switch.

I presume you mean connecting the GSM into the circuit before the big red switch. My misgiving about that was that the GSM switch is then powered unless you switch it off at the fuseboard. Is that safe? If so, it certainly sounds like the simplest and most effective approach. But surely it defeats the idea of having an isolator switch?

Just wire it so that the common and normally closed are in circuit so when it is off (at rest) the heat will be on, and should the GSM switch fail, and I'm assuming it will reset or return to default if it does, then at least you will have heat.

I don't think I get this. Doesn't that mean the heat is on whether the GSM relay is on or off? Unless you mean that the heat is on when the GSM relay is off and the big red switch is on. Maybe that could work (although compared to your first idea I still have to remember to switch the big red switch off when leaving, and there is still no isolation).

Also a single pole 2 way (change over) switch would do you, if you really want to be able overide the GSM switch, just run the live to the GSM switch and loop out to your SP (L1) switch and from that (common) out to your heat and , hey presto, manual overide.
I just feel that having to remember to switch it to "remote" when you go out somehow defeats the purpose of having the R/C option in the first place.

See my CRAP drawing, :) I didn't bother signing up, rushing, so its in some album or other.

http://imgur.com/a/r6rT9

Yes, that looks like it would work, and using a simpler switch. The reason behind my DPDT switch was that the GSM Switch is totally isolated when off, i.e. no live connection. I'm probably just being scared of my own wiring. :)

PS. Just going out the door...........Even a single one way SW would do you, just put it across the common and the normally open of the GSM and mark it "MAN/REMOTE".

That makes total sense. For some reason it never occurred to me to use the GSM device's own two-way switching. I've shown the additional switch across NC and NO below but it's the same thing. That switch is closed for manual operation and open for remote operation. Does this look right? It certainly makes the switch wiring trivial compared to my earlier Rube Goldberg machine. Also I keep my proper isolation switch. And I can leave the whole thing GSM operated all the time (unless I need to switch to manual in case of loss of phone coverage while I'm in the house).

23SpczY.png
 
That makes total sense. For some reason it never occurred to me to use the GSM device's own two-way switching. I've shown the additional switch across NC and NO below but it's the same thing. That switch is closed for manual operation and open for remote operation. Does this look right? It certainly makes the switch wiring trivial compared to my earlier Rube Goldberg machine. Also I keep my proper isolation switch. And I can leave the whole thing GSM operated all the time (unless I need to switch to manual in case of loss of phone coverage while I'm in the house).

23SpczY.png


No, its not quite the same thing, in your drawing you are still relying on the relay contact from common to N/C and then through your switch to heat, whereas if you go across common to N/O (heat) with switch, then you are not dependant on relay contact.
I still think it somewhat defeats the purpose to have to remember to switch over from manual to remote everytime you go out and want to have R/C.

BTW have you checked the load capacity of the R/C to make sure it can carry the load OK. Also what is the rating of the MCB/Fuse feeding the "big red switch" ?
 
No, its not quite the same thing, in your drawing you are still relying on the relay contact from common to N/C and then through your switch to heat, whereas if you go across common to N/O (heat) with switch, then you are not dependant on relay contact.
Fair enough. Switch would have to be faulty for it to be a problem but I'll wire it from CO to NO anyway.

I still think it somewhat defeats the purpose to have to remember to switch over from manual to remote everytime you go out and want to have R/C.
But I don't think there's an alternative that doesn't have the GSM Switch always on, without any switch except the fuseboard tripswitch. Sounds dangerous. The way I'm proposing I can leave it switched to "remote" all the time and use text messaging even in the house. So it will effectively always be on remote, I won't have to switch when leaving.

BTW have you checked the load capacity of the R/C to make sure it can carry the load OK. Also what is the rating of the MCB/Fuse feeding the "big red switch" ?
The switch is rated for 10 amps. My heating is only a couple of pumps and some electronics -- I don't think it could be drawing anything remotely like a couple of kW, probably a small fraction of that. I don't know what the fuse rating is, but I'll check.

Thanks for the thoughts (and the switch simplification earlier, which makes things much easier).
 
The existing double pole heating system switch is wired a little more complicatedly than I was expecting. Here is it from outside and inside:

f5d6U1m.jpg
CtobHfW.jpg


Schematically it looks like this (markings are taken from the switch itself, and shown in approximate positions). There are also similar neutral wires, omitted for clarity (2 "in" wires connected to a single terminal, 1 "out" wire separate):

nxTjLCR.png


I'm a bit confused about how there can be two "in" cables and a single "out". Is the "in" not the power supply from the fuse board?

I can wire my "outs" as originally planned, but I'm worried I'm misunderstanding something.
 
Most likely it is just carrying on to feed another live in and is just tailed from that spur.
 
The existing double pole heating system switch is wired a little more complicatedly than I was expecting. Here is it from outside and inside:

f5d6U1m.jpg
CtobHfW.jpg


Schematically it looks like this (markings are taken from the switch itself, and shown in approximate positions). There are also similar neutral wires, omitted for clarity (2 "in" wires connected to a single terminal, 1 "out" wire separate):

nxTjLCR.png


I'm a bit confused about how there can be two "in" cables and a single "out". Is the "in" not the power supply from the fuse board?

I can wire my "outs" as originally planned, but I'm worried I'm misunderstanding something.

The 2 "ins", as you call them, are standard enough and are just loop on feeds to some other circuit/s, maybe control valves, thermostats,pumps, etc.
Just make sure that you keep them together when making your changes and do not mix them up with the switch wires. A little bit of tape will be handy here to mark them or keep them together.
 
Thanks guys, makes sense. I don't think I need to touch the "ins" at all, I just need to take off an additional neutral out. Only the live out gets replaced, with the wiring to my new switch being inserted in between.
 
Well, I've finally done it. Just turned my heating on by text message for the first time. The arrangement isn't the prettiest for now, but I have plans to tidy it up:

cETxSQH.png


GSM switch at upper right is wired across main heating switch at left. The switch hanging down from the grey wire switches between "manual" and "text message" control. The pair of light switches at centre are on the same backing box as the heating switch, so I can neaten things by replacing them with a triple, one of which will replace the hangy down switch. The GSM switch will have its cover put on and be mounted properly to the wall.
 
Hi
I wish to hook my heating up to an sms unit myself.i have the same apt timer shown in the photo above. Does the sms unit override the timer?
I went onto the texton side but cant see any diagrams on how to wire it.does any one have one or any idear how its done
 
Well, I've finally done it. Just turned my heating on by text message for the first time. The arrangement isn't the prettiest for now, but I have plans to tidy it up:

cETxSQH.png


GSM switch at upper right is wired across main heating switch at left. The switch hanging down from the grey wire switches between "manual" and "text message" control. The pair of light switches at centre are on the same backing box as the heating switch, so I can neaten things by replacing them with a triple, one of which will replace the hangy down switch. The GSM switch will have its cover put on and be mounted properly to the wall.

Does this by pass the clock? I have the same one.does the timer have to be set to on all the time than you text on & the heating comes on.please help.new to this
 
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