Device to remotely turn a thermostat

[Corvl]

My house is getting all automated by now , thanks to vera and Z-wave. And now Arduino comes into play !!

My heating system is also automated , by means of Fibaro relais which turns things (the system itself or pumps) on and off. And radiators have danfoss Z-wave thermostats attached to it.

But my floorheating ..... that was a different story. It had a special thermostat with a temperature sensor going a device which measures the water in the floorheating system.

Allready demolished a danfoss Z-wave thermostate , trying to make the tempretaure sensor external , but no joy.

Huray for Arduino.

Building the gateway was easy enough, building a servo-actuator with an arduino UNO was also very easy.

On vera there was an issue with the slider , with the slider the servo only moves 90 degrees. someone helped me changing some code on the sketch:

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fixed it by replacing the line:

myservo.write(SERVO_MAX + (SERVO_MIN-SERVO_MAX)/100 * val); // sets the servo position 0-180

by the following 2 lines of code:

    val = map(val, 0, 100, 0, 180); // scale 0%-100% between 0 and 180)
    myservo.write(val);       // sets the servo position 0-180

---

Now the servo was moving the full 180 degrees by means of the slider.

Than came the mechanical part, I had to make quite a bracket to hold the servo. Initially I had a standard 3 kg/cm servo , but it wasn't enough to completely close the valve. I ended up using a big scale servo with 14 kg/cm on 7V. Offcourse the servo is powered by a seperate 7V, max 5A power supply

Initially the plan was to attach the servo directly to the thermostat , at that time I didn't know the themostat not only turns , but also moves in-and outwards .....

Plan 2 was to use a timing belt system with 2 sprockets , also this didn't work , because the servo pulled the thermostat towards it

Plan 3 finally worked , I routed out of trespa a bracket where the servo could go freely in and out , but not turn itself.
This trespa ( white) attached to the metal bracket. Now the servo can do it's normal thing , turn the lever , but also move in and outward

Here 2 pictures:

A succesfull project I must say

[hek]

Wow, impressive!

[tbowmo]

@Corvl
Nice mechanical build

You could get electrically controled valves instead, for example a Danfoss TWA-A 24V NC, Still have the arduino control it through PWM..

[RJ_Make]

@Corvl Very Nice.

[Corvl]

Thanks for the nice words

@ tbowmo: ......ohhhhhh , didn't know they existed , that would have been even a neater solution ( and probably quicker) , anyway , my system is working now.

Cor

[Corvl]

one more question.

Controlling the thermostat I have a picture on the GUI and authomation app on my android of a window with curtains..... any possibility I can change this with another Icon, Just to make it a bit more perfect

thanks,
Cor

[Corvl]

Answer to myself:

I use now Imperihome , with that you can use your own icons