Help connecting wireless thermostat to boiler

I may have fallen over at the first hurdle.

I've just received delivery of:

I may have mentioned that the boiler is right at the back of the garage extension. The lounge is at the front of the property, and the internet hub is in the hall the other side of the lounge, but still a little way (another room, external wall) from the boiler.

With my smartphone I do not get wireless connectivity from the boiler room to the internet hub in the hall.

If I've understood the system correctly the Drayton room thermostat has a wireless connection using Zigbee but if WiFi won't reach then neither will Zigbee.

It will also require WiFi from the smartphone to the hub to program.

Thus unless I can come up with a better solution I'll end up putting the thermostat in the utility room and standing in the utility room to program it all, not ideal.

Do you mean just connect 240v across the controller terminals before trying to connect to the boiler? I thought it would need the boiler's connectivity to operate.

I wonder if you could place the hub wherever is most convenient for its use, hopefully where there is also good wi-fi, and run what may be lengthy cables from there to the actual boiler.

Chris

Good thought but when the extension to the garage was built (two owners ago) the facilities (pipes, cables) were threaded in from the corner of the bungalow into flat roof void before putting the ceilings in. When we wanted to separate the shower fan from the garage light on/off switch the electrician said it was just too much work.

An external route would be easier but unsightly and bring its own problems.

maybe their smart plug as a range extender?????

They do one of these but really expensive

you might use this sort of think...

It just needs 240v. It then connects the outputs to the boiler. The only feedback is from the system is via ZigBe from the valves and thermostat.

Dave

I've received the Drayton Wiser Thermostat Kit 1, and whilst deciding how to finalise where the hub will finish I've wired it up temporarily.

My temporary setup doesn't work. I run the App which says to press once the Setup button, a green light is supposed to come on but nothing happens.

It's hard to see that I can have done anything wrong but then again.

A photo of the connections is at:

Any clues? Faulty unit? Any other way to test it?

OK that looks a bit different from the Hive arrangement since the hub bit that talks to a network, and the receiver bit that talks to the boiler would appear to be in one unit rather than two. It also does not appear to have a wired ethernet option, only wifi.

(note I have not had much chance to look at the manuals in detail)

Not always a given - zigbee has a theoretically smaller range, but is a more robust protocol. If should do up to 20m ok.

There is probably not a direct wifi connection between the hub and the phone. Both will need to connect to your router, and that will be the path between them.

It sounds like the hub needs to connect to the boiler via the thermostat input. In many places that already have a wall mounted stat, that will often have a standardised back plate, that would allow the hub to be mounted on instead of the stat.

Since you don't have a wired stat at all at the moment, you don't have that easy option, but on the bright side, you are also not constrained by its current location either.

Yes. Power to the hub should allow it to join the wifi, and hence talk to the phone, as well as to establish a zigbee connection to the room stat.

Not really - all it is doing is sending a signal to the boiler to tell it to fire or not - it won't actually care if the boiler is listening or connected!

In the final setup you would probably wire the hub such that it draws power from its connection to the boiler, as well as feeding the "call for heat" signal back down the same cable. However for testing purposes it only needs power - would could from a plug and a length of flex.

So if you find a place in the room where the hub can see the wifi, even if it is the other side of the room from the boiler, then the install is still quite easy - one three core flex from the boiler to the hub - but all in the same room.

If you can't get wifi at all in the room, then you would have a choice of moving the hub to a room where it can see wifi, but having a longer cable route back to the boiler, or fixing the wifi so that it works in the boiler room.

If it were me, I would fix the wifi so that it works perfectly in every room in the house, since that would make the wiring easier for the hub, but also bring other benefits for other uses.

Obviously getting decent wifi is a whole other rabbit hole to bolt down, but we can look at that if you want to anyway, or can't find a way of getting wifi access to the hub.

Does that two core flex just connect from the two terminals in the boiler to the two terminals on the hub?

If so, then I would not expect it to work at all, since the stat terminals on the boiler will be one 240V output, and one 240V input. The stat is expected to either look like a switch - joining those two connections when it wants heat, or it can just act like like a selective mains supply - supplying 240V down one wire when it wants heat (i.e. that 240V does not *have* to be sourced from the other terminal).

Neither of those terminals would look like a proper neutral. So the hub would probably not have power at all.

Yup, Personally I would start without even involving the boiler by connecting the L & N on the backplate of the hub to a flex plugged into the mains with a 3A fuse in the plug. That should allow the hub to power up, and you can get it talking to the network, and then it can talk to the app.

However if you want to do it with the boiler connected, then you need a three wire connection from the boiler to the hub. Basically L & N out to the stat, and then call for heat back from the stat to the boiler.

So looking at that boiler connection:

The L could come from either the fused side of the top connection - i.e. the "br" terminal, or from the terminal labelled "1" on the connector.

Lastly you need to connection from the hub (pin 3 probably) - the call for heat into the boiler - the one labelled 2

If calling for heat then the switch would close and both terminals would be at the same voltage.

I would expect mains to go into Pins 1 & 2?

We have TPLink smart switches for turning off appliances that don't need to stay on standby, and to monitor their power usage.

The one for the microwave is on a socket about 50 cm from the microwave. Every time the oven is turned on, I notice the TPLink's wifi light starts to blink, showing loss of sync with the router. As soon as the microwave stops, the wifi light comes back on properly.

Looking at Amazon reviews for this kit, they are overwhelmingly positive, but some of the 1 star comments show that they can be a real pain if it all goes haywire.

Chris

Doh!! I had quite misread/misinterpreted both you and the instructions. Copy/pasting into a document and a legible size plus your guidance and the system seems to be functioning. I only say "seems" because it's on when I say boost or increase temperature but it remains to be seen if the schedules etc work over a few days.

I now understand all the other wires that are obviously there for the inbuilt boiler timer. I've left them there and put the timer "always on" and at a high temp. I presume that's ok.

Read my response to Chris Dixon's earlier post regarding locating the hub etc. Some positive news on that front too.

Well you had my brain ticking over there. The people who had the extension built. two owners ago probably retained the original house boiler. The current boiler was put in by the last owner who was always cash-strapped. That made me look more closely at the box behind the jackets that are hung up in the pantry. An ACL Drayton. Go back to the boiler and there is an unconnected cable, the one that would have connected to the pantry controller.

With John Rumm's help wired it all up and working.

So location is now not an issue, it is near the lounge, good wireless and Wi-Fi signal and of course I could use the existing backplate.

Brilliant - thanks for sparking my brain to investigate.

Glad you are making progress, we are always learning.

Interested to hear how it all actually performs for you.

Chris

Good result, well done.

Well if it was off at some point, and then fired at another, it would suggest it has control over it in both directions. So that is pretty reassuring.

Yup, always on is fine. If the temp is the boiler flow temp, then you can probably have that set fairly low (50 deg say) this time of year.

ok will do...

Yup, could make an interesting wiki page if Anthony does not mind writing a few words.

Oh, that's the opposite to the way my brain was working. I thought just leave it on high and let the stat control things and never touch it again. Having said that I've just been to look and with the dial at around the 2/3rds the temp got to 50degC. What am I aiming to achieve here, smoothness ie longer periods on rather than overshoots and lots of on/off cycles?

Lounge is set for 20degC till 2230. Probably wouldn't have had the boiler on yet (usually try to wait to the end of September) but obviously got to try the new setup. 15deg overnight, 19deg 0630-0830,

It'll be interesting to see what happens when I install the app on SWMBO's smartphone. She would never go to adjust the boiler but I bet there'll be a lot of Boost going on. The intention is to try and save fuel but I now wonder if that's a bit optimistic. I'll need to find the quick anti-Boost setting (Away Mode possibly). Investigations for another day.

The higher the flow temp, potentially the more loss in the pipes too. I was always told (by our CH guy) to keep it as low as possible consistent with enough heating and hot water. Higher in winter.

I also believe that condensing boilers are more efficient at lower flow temps, but I'll let someone else comment on that.

Well that would certainly work, however there are downsides in doing it that way.

You have a boiler that can modulate (i.e. vary its output power to match the demand), and it is also a condensing boiler. So it will achieve higher efficiencies with lower return water temperatures (since these dictate how cool it can get the exhaust gases and in turn how much latent heat it can extract from them).

So longer burns at lower power will mean:

Narrower temperature swings, and fewer overshoots. So more comfortable, and less overheating.

Less clanking and clicking noise from expanding rads and pipework.

Yup a setback temp of 15 deg is quite common. In most properties that means that the boiler is unlikely to fire at all at night. (depends a bit on how fast the places loses heat)

:-)