Wireless thermostats with central control unit

[mishoboss]

Hi, I hope on some help and product suggestions for my case. I have a central heating in my new apartment with radiators in each room. I want to smart control each room's temperature with smart thermostats or any other interface wirelessly (RF433/ZigBee/Z-wave/Other?) connected to a central control unit. I have mounted a Honeywell thermo valves in my collector box. They operate at 230V AC in normal close (NC) mode.
This is my collector box:

IMG_4770.jpg (75.45 KiB) Viewed 10945 times

What I need is wireless communicating thermostats or just interfaces (without thermostat logic built-in) and a central control unit with 6 or more 230V relay outputs. Also I need to communicate with my heating system somehow (RS232/RS485/Ethernet/ZigBee/Other?), so I could control it via software on Linux server (I can write this if I have the protocol specs).

I draw a sketch to illustrate how I see all this would happen:

thermostats.png (15.1 KiB) Viewed 10945 times

Could you suggest me some products for this case, that could be found in Europe and not be enormous pricey? I'm not afraid of making my hands dirty with building or modifying some hardware.

Also I would be happy to see other options and suggestions for best smart heating solution in that case.

[John]

Hi,

I have the same problem (domoticaforum.eu/viewtopic.php?f=17& ... ohn#p43276) and was thinking of replacing the honeywell valves.

What type of valves are in your system?

John

[b_weijenberg]

This 433.92MHz sensor can have up to 7 wired 60015 temperature sensors connected http://www.rfxcom.com/sensors.htm#40066
Instead of the 60015 you can also use DS18B20 sensors.

[mishoboss]

Thanks, but this is just a wireless sensor with one wire interfaces. There's no PID regulator, there's no interface to set desired temperature, there's no LCD screen to show current temperature and so on. I need a good looking interface to set room's temperature.

John, I saw your post. I don't think there are Z-Wave valves out there. What thermostats you have? How you want to control heating?

[John]

I have HCW 22 (Honeywell, wireless thermostats) and a HCE 60 (Honeywell, heating controller).
In the future I want to expand the system with Zwave-zigbee/RF thermostats an valves. When the system brokes down I want to relace it completely.
What type of valves do you have? In my situation the valves are open or close and the temperatures are controlled very well within the rooms.
John

[Verkenner]

Real soon Plugwise can help you with temperature meassuring in every room and switchers.
I have seen the working demo systems ! Very nice.
Send mail to helpdesk@plugwise.nl to ask them.

see www.plugwise.nl

Best regards, Verkenner

[mishoboss]

@John - My valves are the same - normal close when there is no 230V supply and full opened when there is supply voltage. They were cheap, about 10 Euro each.

I know Honeywell's HCW 22 and HCE 60, but they are extremely high-priced in my country (120 Euro for HCW 22) and there's even no LCD for that price. There is no way for two-way control (from local wall-thermostats and from remote server), there's just one knob...

@Verkenner - Could you please, tell me a little more about what you've seen? Thank you.

[Verkenner]

I have seen Sense Lite (indoor), humidity and temp.
I have seen Scan (indoor), motion detection.

Plugwise will present them. soon

Regards, Verkenner

[mishoboss]

Thank you for the info. Unfortunately this is just a sensor, not interface to set and control room temperature, right? It's just a part of the whole system... and I can't find the other parts.

I'm sure there must be a product out there containing wireless thermostat interfaces and relay control unit with some kind of PC communication (see the graphic in my first post).

[Verkenner]

Hi mishoboss,

You can find the products on www.plugwise.nl.
Of course the magic (control) is in the SOURCE-software.
New release of SOURCE is comming.

Regards, Verkenner

[Tiz]

Mishobos,

most automating systems will be organized a little differently. The PC will receive information from sensors and will activate actors. This can both be done through different interfaces. A user control interface will also be directly connected to the PC that can control the actors (or show read out values of the sensors). This setup is far more suited for extension in the future.

So in short, I would replace the control unit in your diagram with the PC and have a user interface connected to that PC.
If you do it like this you can choose a hardware interface to the different items and do not have to look for very specific hardware that:
1 - has some sort of graphic UI usable for your application
2 - has wireless interfacing posibllities on its inputs
3 - has 230V ?A relay possibilities on its outputs.

Hope you understand what I am trying to say.

[mishoboss]

Hi, Tiz,
thank you for your answer. I have thought about that you said. It's really nice solution, but it misses some things again. This is how I see your suggestion:
1. Use some kind of control interfaces that communicate with a PC
2. Use some kind of wireless sensors that also communicate somehow with this PC
3. Use some kind of relay board attached to the PC with serial/USB/Ethernet
4. Software that takes data from the sensors and data from control interfaces and do PID math and controls the relay board

This is very challenging thig as I see it. All these hardware will speak different language that this software must understand and take some decisions. I don't know such a software.

The wall interfaces are another problem. The only thing that comes tomy mind is to use some tablets or Nokia N900 that communicate via http with the server. Other that comes to my mind is using some ZigBee buttons that send commands. Either ways I can't see this system to cost bellow 1500-2000$.

[Tiz]

About the software, Homeseer together with some plugins can handle this. Maybe you can look around in the Homeseer section of this forum for details because I do not use Homeseer myself and am not a specialist.
I am writing my own software to do things the way I described. But I must admit that if heating is the only part of home automatino that you want to implement, my suggestion might be overkill for your situation. A different solution that comes to my mind is to look around in the Arduino section of this forum. Arduino has optional xBee modules for your wireless part and has also standard IO's that will enable you to switch some relais. And since Arduino is a development platform, you can customize the setup to your needs. Most probably you won't need a PC either.
But whichever way you choose it will involve quote some DIY work to prevent cost from rising too much.

[bartg]

Hi Mishoboss,

What you are asking for is exactly what I have build on my house. I have 25 valves in my system which are operated by Normally closed servo motors. I use a PC with HomeSeer software as central contoller. The sevo motors are operated by ClickOnClickOff AC1000 220V switches. The temperature is monitored by Oregon Scientific sensors in every room. HomeSeer can receive and send with a RFXCOM receiver and transmitter. The script to control the heating is self written with scripting in HomeSeer.

I am still tuning the scripts and make a user interface in an Ipod so everybody in the house can control there own room temperature. So far I have focussed on keeping the temperatures constant at the selected setpoint.

Water temperature in and out of floorheating

water temp in out.JPG (15.89 KiB) Viewed 10787 times

Regards,
Bart

[bartg]

More pictures:

I created a virtual device to set the temperature for each room. The status includes:
- Requested temperature
- Status of servo motor
- current room temperature
- room temperature 30 min ago
- room temperature 60 min ago
- room temperature 90 min ago

Setting the required temperature

Verwarming setting.JPG (148.58 KiB) Viewed 10787 times