Adding Some Heat Into My Relationship With Vera
Danfoss Living Comfort Thermostatic Radiator Valve.
Living in an old house, with only one and a half thick brick walls with no cavities or insulation, our home loses heat like you would not believe! And the worst room of all is my daughter’s bedroom which has 3 external walls, each one competing to suck out all my expensive hot air.
So in an attempt to help my other half, who had become almost OCD like in her approach to the monitoring and then deciding the specific value(s) the radiator valve needed to be, i decided to install a Danfoss Living Comfort (Z-Wave) Thermostatic Radiator Valve.
The physical installation was surprisingly easy thanks to some fixing options that came with it and its inclusion into the MiCasaVerde Vera was also pretty straight forward as well, the latter resulting in a nice virtual thermostatic device appearing on the dashboard. The new device allows me to increase and decrease the required set point values, although you can still do it manually using the + – controls on the top of the unit.
One immediate disappointment was that the virtual device did not show the actual room temperature even thought it has the ability to do so. Unsure why this was the case, after I thought about it a bit more I can only assume that it must just be very difficult to do, especially considering how close the valve is to a direct heating source.
My next challenge came when I tried to control the Living Connect via the Vera user interface (UI) not only is this influenced by being a battery powered device, which means it sleep for extended periods of time to preserve its longevity only waking at pre-set intervals to check for any messages. I also found out that (sadly) the Danfoss unit does not respond very quickly to a new set point commands, when compared to how it behaves if you enter them manually!
Wondering if it was just me I decided to trawl the forums to see if I was alone in this or if there were others venting similar frustrations. Sadly it didn’t take me long to see I was not alone and what worried me more was that some were seeing delays of hours before the valve would react.
Tempted to remove it and send it back, I decided to carry on regardless as my experiences with Z-Wave have rarely ever been easy or straight forward. In fact, I’m sure perfectionists like Steve Jobs would never have allowed such things to pass into a consumers hands if it wasn’t the epitome of function and form. Oh well, i guess this is the price you pay for straying into the niche world of Home Automation.
After some further reading online my interpretation of the messages and posts from others and from Danfoss themselves was that. “A command sent remotely is only seen as a desire to change the set point temperature, and as such it’s applied slowly over an extended period of time, by using macro turns of the valve’s internal mechanism. Where as a directly inputted request is seen as an instant requirement and one that the valve will try to react to instantly.”
Danfoss also seemed to suggest that such macro turns over an extended period help to preserve the batteries more that reacting instantly, but as such a change can take a while, it might not be for everyone. I personally would add, that a thermostatic Radiator Valve itself can not be seen as a precise instrument, it’s reliant on a pin going up or down in order to open or close the value, so any restrictions in how that moves should also be factored in, especially when you’re looking to move it by just a degree or two. (A small piece of grit or rust could easily effect things)
Accepting that I don’t live in a perfect home, nor do i have a perfect HA set up or radiator valve, I decided to keep it and see how it works over an extended period of time.
UPDATE : A big thank you to an now ex MicasaVerde forum guru (AP15e) who has created a script that would allow the Danfoss Virtual Thermostat to show the temperature reading from another temp sensor in the room. (Great Job!)
Next – Integrating the Horstmann Wireless Room-stat
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