Wireless room thermostat: wiring for the receiver.

[b33k34]

Now this, on the other hand....

http://www.nest.com/why-we-made-it/index.html

What the man who invented the iPod is doing now.

 

[Myson700B]

Now this, on the other hand....

http://www.nest.com/why-we-made-it/index.html

What the man who invented the iPod is doing now.

Is the following inconsistent?

"Our thermostat is $249 and will ship soon."

Customer Reviews

Shanna,
Homeowner from Keysville, GA
October 01, 2011

I received our power bill this week for the first time since we installed the Nest Thermostat. It had dropped $40.

 

[ban-all-sheds]

Not necessarily - not if they don't pay attention to updating their website.

Can you buy it?

Interesting idea, but you can patent code and hardware, you can't patent ideas.

This is cool though.

 

[Myson700B]

Apple has a name for it already: iGlass http://www.infoworld.com/d/mobile-technology/apples-amazing-iglass-revolutionizes-mobile-again-026

 

[ban-all-sheds]

I don't think Corning were perpetrating an April Fool's joke though..

 

[Myson700B]

Indeed. We may see some of the glass based applications breaking out

On the topic subject an electrician said that I could use the wiring the thermostat currently uses and wire the receiver there.
I need to check with my electrical multimeter that there is a live, switched live and neutral wires for that.
I assume that there must be a switched live because the current wall thermostat, a Drayton Digistat 3, needs that.
Its a while since I used my multimeter so I'll have to mug up on how to do the testing of the wires.
The wires are:
Yellow connected to terminal 1
Red to terminal 3
Blue unconnected
Green unconnected (looks like an earth wire)

 

[Myson700B]

The mains AC at 240V for the current battery powered thermostat flows between terminals 1 (yellow wire) and 3 (red wire, switched)
The proposed SCR Receiver needs mains power so I intend to connect terminal 1 to N and 3 to L.

Would the team confirm that this is correct please?

 

[ban-all-sheds]

Seems unlikely to me.

Your current thermostat switches the 240V supply to the boiler, but it itself is powered by a battery.

The new one is powered by a 240V supply, which you don't have there.

 

[Taylortwocities]

The new one is powered by a 240V supply, which you don't have there.

You might have, but you will need a multimeter to confirm that the blue is neutral and if the red (or the yellow) is a permanent live.

 

[Myson700B]

Seems unlikely to me.

Your current thermostat switches the 240V supply to the boiler, but it itself is powered by a battery.

The new one is powered by a 240V supply, which you don't have there.

The current thermostat is indeed battery powered. However when I put my multimeter across terminals 1 (yellow wire) and 3 (red wire) it showed AC 240V.
That's why I proposed connecting terminal 1 to N and 3 to L.
However I'm thinking that one of those terminals is the so called switched live so I may indeed have to test if the blue wire is neutral and only if so use it to connect to terminal N.
Also I don't currently know if the red or the yellow is the switched live.
And what does volt free contacts mean?
Confused more than ever.

Earlier on in this thread it was written that I should install it at the boiler's wiring centre.
I currently have an external Horstmann Centaur Plus C27 heating programmer wired to that centre fitted after the original Myson 700B electro-mechanical programmer on the boiler's front panel failed. The C27's installation wiring is here http://www.horstmann.co.uk/downloads/ElectronicDocuments/Central-Heating/C27-InstallerGuide.pdf.
So when I get the front panel off the C27 (the screw fixing it is currently problematic) I'll check how it is wired.

 

[ban-all-sheds]

The current thermostat is indeed battery powered. However when I put my multimeter across terminals 1 (yellow wire) and 3 (red wire) it showed AC 240V.
That's why I proposed connecting terminal 1 to N and 3 to L.

OK.

Could you get your video cam out and film it when you turn it on - it might be spectacular.

And what does volt free contacts mean?

It means that they don't output anything of their own accord - they are just switch terminals - you can use them to switch LV or ELV.

Think of a lightswitch - that has volt free contacts.

 

[EFLImpudence]

Myson -

It's been six days since your original question.

What you have to do is remove the Horstmann which is currently fitted at the wiring centre and replace with the new timer/programmer.
It may even fit on the same back-plate; it may not. I can't be bothered to look.

Then, at the boiler, you remove the two wires that run from the present thermostat and fit a short link between the terminals to which they were connected.

Remove or make safe the now REDUNDANT cable from the boiler to the hallway.

Repair hallway wall.

Sit down wherever you want and practice with the sender unit.

 

[Myson700B]

Could you get your video cam out and film it when you turn it on - it might be spectacular.

So I held one end of the wire in my left hand and the other end in my right hand?
Here's what happened: http://205.243.100.155/frames/mpg/500kV_Switch.mpg

It (volt free contacts) means that they don't output anything of their own accord - they are just switch terminals - you can use them to switch LV or ELV.

Think of a lightswitch - that has volt free contacts.

Ah! to make and break a continuity in a wire? I assume that domestic light switches have a mains supply circa 240V whereas the switch between volt free contacts of the SFC will not handle 240V.

Time to call that electrician back.[/url]

 

[Myson700B]

EFLImpudence,

Thanks for the detailed instructions. I should have acted on your first reply posted: Sun Oct 23, 2011 7:28 pm.

Also thanks to all others for their replies.

 

[Myson700B]

Then, at the boiler, you remove the two wires that run from the present thermostat and fit a short link between the terminals to which they were connected.

Sorry to persist. But what does that do?