DAK - About home automation?

[JMN2]

cooper and hunter? There must be loads off apps from mobile and internet, because in Scandinavia they are banging on about it a lot.

[killergorilla]

You could buy a wi-fi thermostat which would control heating and hot water. Honeywell products are excellent (no connection other than happy customer)
A more expedient way may be to buy a d'link wifi plug and then plug the immersion heater through it.
This way you can have the timer turning the heater on, but no power to the heater so it would effectively be dead. Control that via the d'link app and you're set. Probably cheaper than a thermostat or timer and less disruption to existing electronics.
Hope that's of some help
KG

[JMN2]

If air heat pumps and ground source heat pumps can be controlled via gsm to wifi then why not an immersion element in a tank of water?

[Slarti]

Sorry, I didn't know whether this topic belonged here or in building/DIY or in computers, please bear with me.

Anyhow, I have what seems on the face of it a very simple home automation job to work out. My son has a flat with two immersion heaters in the water tank, one is connected to a conventional Siemens time controller, as used on a wet heating system. (The other one is switched manually to boost the hot water if required). I'm happy with this, but the flat occupancy is not as regular as we had anticipated so the conventional Siemens time controller, (about 14 years old and working fine) could do with upgrading to one we can control remotely from an app. From the research we have done, it seems that the all domestic Siemens time controllers use a common back plate. So, we had imagined that I could simply buy a modern WiFi enabled time controller from Siemens. The intention being to fit it to the existing back plate, connect it to the router by WiFi, and instantly, app controlled hot water. But it seems that no such device is available from Siemens. In fact, I cannot find a simple electronic heating/hot water controller that is WiFi enabled of any brand at all. Am I asking too much? It's 2017 after all. There is a seemingly a huge amount of home automation hardware on the market now, quite bewildering. But nothing seems obviously ready and simple to retro fit to our water heater. Any thoughts please on how to do this simple system so that my son can use an app on his phone to tweak his hot water heating?

PS - It's not out of the question that in the future, such a system might be called upon for other automation tasks, but this is not a high priority. Thanks.

Aren't there plugs/sockets that are controllable by an app?

I'm sure I've seen something about a IoT adaptor that you plug into the existing socket and can turn it on/off with an app.

Would that work?

Slarti

[gryffron]

Be careful. An immersion heater is often much > than the typical 3kW which can be sourced from a standard electrical socket. Do you know its rating?

Not saying your job can't be done. I'm sure someone makes a suitable switch. Just that conventional socket controllers which several people have suggested might not be beefy enough for an immersion heater. Indeed, are quite likely to go up in smoke.

Gryff

[richlist]

I agree with Gryffron.....i was always under the impression that immersion heater switches were rated 20 amps not the 13 amps that sockets and standard time switches are rated.

I think it's something to do with the fact that they can draw a high current for a long time so need a higher rated switch.

No doubt the electricians here will be able to confirm.

[vagrantbrain]

A simple way would be to use something like the d-link smart plug to control the immersion heater through a contactor rather than try and pull the load through the socket. Basically the smart plug would switch on/off the supply to the contactor (aka relay) which would then switch on/off the supply to the immersion heater. Not really a DIY job but any competent sparkie that does commercial as well as domestic should be able to make something cheaply.

[servodude]

I know that Nest did some rejigging of their product to be "boiler friendly"
- http://www.wired.co.uk/article/nest-thi ... ion-boiler
- they're possibly overkill and over expensive; but can work

but if you google for "nest alternative" you'll find other options and homebrew solutions

or have a look at the thermostat options on ifttt https://ifttt.com/search/query/thermostat

have fun
- sd

[Itsallaguess]

OK - Here's the first attempt at a system. The only bit I do not know what to buy is the Smart switches. These don't need to have a high capacity, they'll only be switching the relays On/Off.

Just some initial thoughts regarding the flexibility of the system as it's drawn. It looks like both heaters would require 100% control through the network, which isn't, perhaps, something that either you or any proposed visitors might want? Wouldn't you want to introduce some element of manual-operation as well, both for 'on' and 'off' operation of each heating circuit?

You've mentioned the smart-switches, with a view to not knowing what you may need, so I've just taken a quick look on Amazon to see what they've got in this arena, with a view to providing you with access to both the user-reviews and also the helpful Q&A's for each device -

https://www.amazon.co.uk/Wireless-Contr ... B06XKJKQ3C

https://www.amazon.co.uk/HS110-Monitori ... B01IBUF48S

https://www.amazon.co.uk/Wireless-Contr ... B06XYGPVKD

These aren't in any way 'recommendations', as I've not done enough research on the individual items, so the above links are provided purely to be able to dig about in the reviews and Q&A's. I find doing so really helpful at this stage of purchase, before you really know what you want things 'to-do', alongside not knowing what to actually buy...

You might also find it helpful to have a bounce along the 'What customers buy after viewing this item..' links on the Amazon item-pages, as this can also help to find some really useful items that end up being popular for people with similar needs...

Note that the third link does seem to provide some sort of manual-operation, which might suit you for a per-heater 'in-house' situation instead of having to always use the network operation, but again, this is just an example of the things available in this tech-space, and there may be better specific items available for your particular use-case.

Something else to think about is some sort of 'regular-off' over-ride, to help prevent over-runs into stupid times of the night. I've got manual-override controls on my central-heating controller, but also have regular 'turn-off' phases as well, to turn off the central heating at 8pm at night no matter what 'state' the central heating is currently in. Not only is this helpful in keeping bills down, the more important point for me is that the house cools down at that time of night so it's not too uncomfortable to sleep.

Looking at your current diagram, you may be able to do this with your current Siemens programmer, rather than leaving it in an 'always-on' state?

Just a couple of things to think about, but this is an interesting little project so do keep us informed of your progress. I think you've got a neat solution in there somewhere, but I think it needs some more thought before getting the wire-cutters out.

Cheers,

Itsallaguess

[JMN2]

...

As you can see, even though the hot water and the heating are electric, this is a standard heating controller. Why on earth doesn't anyone make a WiFi enabled one of these? It seems such an obvious thing to do....

Same reason why houses with non-return valves and combiboilers without water storage in the attic still don't have one lever mixer taps. Tradition and conservatism.

Fred, I'll stop trolling your thread now

[gryffron]

Rather than contactors or traditional relays you might like to consider solid state relays like these: http://www.ebay.co.uk/itm/1pcs-Solid-St ... 0505.m3226

That one is mains in - mains out, output rated to 75A!. You can also get low voltage DC actuated ones if that suits your setup better.

I've used the DC in/out ones. They're much more reliable than traditional mechanical relays.

ATB
Gryff

[csearle]

I agree with Gryffron.....i was always under the impression that immersion heater switches were rated 20 amps not the 13 amps that sockets and standard time switches are rated.

I think it's something to do with the fact that they can draw a high current for a long time so need a higher rated switch.

No doubt the electricians here will be able to confirm.

I don't agree with his statement:

An immersion heater is often much > than the typical 3kW which can be sourced from a standard electrical socket.

In my experience domestic immersion heaters are seldom more than 3kW.

In the UK the ratings of switches/isolators tend to be 10A for lighting, 20A for general applications, and 45A for cookers/showers.

So, providing the immersion heater is rated at 3kW or less then any suitably rated relay or wirelessly controlled socket/switch could be used. [Edit: Actually the 3kW clause here is redundant.]

As to whether the immersion heater is run off a standard final circuit (ring or radial) I'd say there is nothing inherently dangerous in doing so. Especially if the system involves a tank stat that will turn the load off periodically.

When erecting a domestic electrical installation known high loads are usually supplied with a dedicated circuit for maintenance purposes and to prevent the longer-term nature of their loads from invalidating the diversity that had been accounted for in the standard circuits.

Regards,
Chris

[richlist]

csearle, I accept your superior knowledge on this matter however, all of the standard immersion heater switches I have ever bought and replaced in my rental properties have all been dp rated 20amps.

I have one on the desk in front of me now....it says it's 20 amps.

I have bought properties where previous owners have fitted standard 13 amp dp switched fused units to control immersion heaters and they have all resulted in burnt terminals so have always replaced them with 20 amp rated switches.

[csearle]

csearle, I accept your superior knowledge on this matter however, all of the standard immersion heater switches I have ever bought and replaced in my rental properties have all been dp rated 20amps.

I have one on the desk in front of me now....it says it's 20 amps.

Seems reasonable, as I said, switches (not for lighting) tend to be 20A.

I have bought properties where previous owners have fitted standard 13 amp dp switched fused units to control immersion heaters and they have all resulted in burnt terminals so have always replaced them with 20 amp rated switches.

That could be because of poorly made connexions at the terminals. Replacing a fused-connexion unit with a switch/isolator should only be done if it has been established that the fuse wasn't included there specifically to protect something*.

Regards,
Chris

* For example the fuse or circuit breaker at the fuseboard was dimensioned to protect a larger cable to the fused-connexion unit, but too big to provide adequate protection against over-current in the immersion heater or its smaller cable.

Another example is where the power is being supplied from a standard circuit where it must be limited to one 13A load.

[ReformedCharacter]

Sorry, I didn't know whether this topic belonged here or in building/DIY or in computers, please bear with me.

Anyhow, I have what seems on the face of it a very simple home automation job to work out. My son has a flat with two immersion heaters in the water tank, one is connected to a conventional Siemens time controller, as used on a wet heating system. (The other one is switched manually to boost the hot water if required). I'm happy with this, but the flat occupancy is not as regular as we had anticipated so the conventional Siemens time controller, (about 14 years old and working fine) could do with upgrading to one we can control remotely from an app. From the research we have done, it seems that the all domestic Siemens time controllers use a common back plate. So, we had imagined that I could simply buy a modern WiFi enabled time controller from Siemens. The intention being to fit it to the existing back plate, connect it to the router by WiFi, and instantly, app controlled hot water. But it seems that no such device is available from Siemens. In fact, I cannot find a simple electronic heating/hot water controller that is WiFi enabled of any brand at all. Am I asking too much? It's 2017 after all. There is a seemingly a huge amount of home automation hardware on the market now, quite bewildering. But nothing seems obviously ready and simple to retro fit to our water heater. Any thoughts please on how to do this simple system so that my son can use an app on his phone to tweak his hot water heating?

PS - It's not out of the question that in the future, such a system might be called upon for other automation tasks, but this is not a high priority. Thanks.

One way to do this would be to use a relay to do the switching and use a lower rated switch connected to a suitable and inexpensive 5v power adaptor to switch the relay. 20A relays are not expensive. That way you can use whatever switch\app you want.

I've been looking into various home automation solutions for some years, Z-Wave, Zigbee and a few others and once had a brief dalliance with X10. The problem with most of these systems is that there has been no single system that can control all the devices that one might reasonably want to control and it is easy to envisage a mish-mash of different technologies that don't work together.

The game-changer in recent years has been the App as a means of control. And in particular IFTTT (If This Then That). IFTTT is an App that runs on a phone. It's purpose is to connect together Apps (and associated hardware) so that they can be used to control each other.

IMHO it's well worth a look:

https://en.wikipedia.org/wiki/IFTTT

I'll give an example. We live next to a road which is unlit and on which cars travel fairly fast. For some years I have been trying to figure out a way for an outside light to come on to illuminate the road in front of our house (it's a safety issue) when my wife returns home and reverses her car onto our property. A PIR will not do this because I want the light to come on just before my wife arrives so she can see and be seen. I've come up with various ways that I might achieve this over the years but all of them were too impractical. My wife recently bought a couple of LIFX bulbs which, as you may know, can be controlled via a LAN or the Internet by way of an App.

I suggested to my wife that she might try IFTTT. Programs that perform tasks via IFTTT are called 'recipes' and sure enough there was one already written and available to control LIFX bulbs according to location (you find a location on Google Maps, and use your fingers to expand a 'zone'). You can set LIFX bulbs to operate when entering or leaving the 'zone'. This was so easy it took my wife about 10 minutes to complete, including downloading IFTTT, to enable a light to turn on when she is returning home and about 100 metres away. It works perfectly and now all I need to do is fit an external LIFX bulb. I think IFTTT is most impressive.

You could for example control a relay with one of these (not a recommendation but a random Google) Wifiplugs:

https://www.wifiplug.co.uk/

Apps for IOS and Android available, and compatible with IFTTT.

RC

[quelquod]

I have one on the desk in front of me now....it says it's 20 amps.

Seems reasonable, as I said, switches (not for lighting) tend to be 20A.

But not (for instance) the kind of programmable switches sold as immersion heater time clocks which are frequently 13A or sometimes oddly 16A. Interestingly I've replaced quite a few of those over the years when (I surmise) the contacts went high resistance and the things melted. Consumer grade 13A kit can be quite iffy - for instance the number of 13A sockets used long-term for tumble dryers and the like which I've had to replace.

[richlist]

Exactly the point I was trying to make.

In theory 13 amp should be ok but in practice it seems not to be so in every case.

[csearle]

Exactly the point I was trying to make.

In theory 13 amp should be ok but in practice it seems not to be so in every case.

I suppose it doesn't hurt to over-engineer. And if in circumstances where the immersion heater spends much of the time on rather than off, maybe through frequent use of hot water, then the 13A fuse itself will generate quite a bit of heat. That heat could conduct particularly to the line terminals and accellerate any corrosion. So I take your (and qq's) point.

And on a vaguely similar subject normal double socket-outlets are usually only rated at 13A too so they are frequently overloaded in some housholds. In fact on the 20th I'm changing out an ancient fuseboard and have already spotted a double socket-outlet servicing a huge tumble dryer and a huge washing machine. I'll be interested to see if there is any trauma at the terminals. If there is I'll post a photo.

Regards,
Chris

[quelquod]

And on a vaguely similar subject normal double socket-outlets are usually only rated at 13A too so they are frequently overloaded in some housholds.

This is a bit of an anomaly which I first noticed years back when casually glancing at the paperwork accompanying IIRC a brass faceplate. How the user is expected to know baffles me as nothing is ever on the face after all. It's not particularly obvious from the construction either why it should be so. I should think it's pretty common in kitchens and utility rooms for them to be overloaded (according to spec anyway).

[csearle]

I should think it's pretty common in kitchens and utility rooms for them to be overloaded (according to spec anyway).

I've come across several double socket-outlets that have clearly been overloaded in this way that have shown actual damage.

For example where the insulation of the attached wires was discoloured black and rigid (quite common); where there has been a discoloured crack between the outlets on the front of the faceplate; where one outlet has not worked (upon dismantling one I found that one of the spot welds linking two internal conductor strips had over-heated and sprung apart; and in one case the white plastic front had a large straw coloured patch where it had over-heated.

Chris