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Hello Chris

Thanks for the interest, yes time clock control would be great to do or maybe temperature curve based control? you could draw using a series of sliders the temperature you want in the room at different hours of the day?

Remote access can be done by using port forwarding on your router, this wikihow here covers it pretty well http://www.wikihow.com/Set-Up-Port-Forwarding-on-a-Router

Point 3 also needs some work but yes agreed it would be good and also I agree on distributed intelligence for most of it and emoncms for the things that cant be done on the nodes themselves as you say.

At the moment there are these basic examples built on top of packetgen http://openenergymonitor.blogspot.co.uk/2013/12/emoncms-control-developm... the more advanced things need to be added.

Hi Trystan,

Yes, you're right, you'd want to be able to control the setpoint to vary across the day, with a 'setback' temperature (or off if you want) when the heating not required.

By the way, I've been using one of these actuators to control a radiator from an Arduino;

http://www.heatingcontrolsonline.co.uk/emmeti-m-20.html/normally-open-th...

I have the normally closed version (24V=valve opened). Saves the trouble of using motorised valves (=noise and positional feedback issues). You would need a relay with 5V input to switch the supply to the valve (I've actually used an h-bridge motor driver, as the current is small). I'll soon be logging room temps to see how well the valve controls temperature.

Thanks for the info on port forwarding, I will take a look.

Chris

The actuator looks interesting, how do you install it, I checked the manufacturer's website but it wasn't clear how it works.

Hi there,
You fit it like a normal TRV head, it just screws on. You have to have the right type of valve or use an adapter. Best to check with them.

I assume the loss from running some kind of transformer and powering the radiators is more than offset by the gains in not heating when you don't need to. Ultimately something I'd quite like to do... how do you power at 24V?

OK thanks, I don't have any TRVs here just standard on/off valves so probably not an option for me.

Yes, the numbers are pretty good. The device uses 3W, I expect the transformer uses a similar amount, but need to test this. For a 1000W radiator you're looking at less than 1% extra energy use. You're right though, don't want this on all day.- hence why I want to be able to switch the system on or off according to time of day.

To control the 24V supply you can used an arduino compatible relay which uses a 5V signal to switch 24V. I'm actually using a h-bridge motor driver which I built onto a prototype board. I'll post some details soon.

As a basic concept of time clock control I've put together a script that updates packetgen with the desired heating state and setpoint for a given day of the week and time of day. No GUI yet but fairly easy to change the settings in the script.
I have attached it below:

To run it just run $ php scheduler.php

Here's the main logic:

    $heatingstate = false;
    $heatingsetpoint = 5;

    if ($dayofweek>=1 && $dayofweek<=5) // Week days
    {
      // Heating period A: 6am to 8am
      if ($hourofday>=6 && $hourofday<=8)
      {
        print "- Weekday heating period A\n";
        $heatingstate = true;
        $heatingsetpoint = 18.0;
      }
     
      // Heating period B: 5pm to 23pm
      if ($hourofday>=18 && $hourofday<=23)
      {
        print "- Weekday heating period B\n";
        $heatingstate = true;
        $heatingsetpoint = 18.0;
      }
    }
   
    if ($dayofweek==0 || $dayofweek==6) // Saturday and Sunday
    {
      // Heating period A: 6am to 8am
      if ($hourofday>=7 && $hourofday<=23)
      {
        print "- Weekend heating period A\n";
        $heatingstate = true;
        $heatingsetpoint = 18.0;
      }
    }

The script needs to run all the time and would be something ran as a service script. Another approach would be to run it as cron but then your limited to 1 minute updates.

Trystan,

I'm not familiar with PHP yet, but makes sense.

The next step would be to set up separate schedules for each room (times and temps), which I guess could be done by adding more variables to the above.
 

Going back to Schism's comment- it would be quite easy to set up monitoring of the boiler flow pipe as a means of determining when the heating is on (e.g., if it rises above 40deg or so). This could then be broadcast to any radiator controllers to tell them to switch on, and would save the actuators being needlessly on when there was no heat in the system. 

Obviously if the script above can be developed that will provide the required function anyway.