Hello everyone. I am considering diving into home automation with lights and locks as my first goal and Hvac a close second goal. I leave my house a lot for weekends so i would like to be able to control and monitor the temp while away. Right now I have one zone and one programmable thermostat that has been great. What a difference it made from the old mercury thermostat it replaced. I have hot water that i am splitting into three zones. Upstairs, Living Room/Downstairs BR and Kitchen/Dining/Bath. Each of these areas will already have 4 in 1 motion sensors. Could I take the temperature from the motion sensors and write my own code that will control three outlets that i will wire in at the boiler. The outlets will be wired to the Taco circulator pumps. Then I could set up multiple scene’s depending on whether were home or away on vacation or home on vacation. Pretty much telling the Vera to turn outlet one on if temp from sensor one drops below 70 between the hours of 4pm to 10 pm. Stuff like that. No thermostat to contend with.
Unless you are very experienced with hydronic heating systems, I would caution against this approach. Not that I’m any expert, but I’ve only ever seen zones controlled with thermal valve actuators, not with individual Taco circulator pumps. Here we have a Basis AB-4001 controlling thermal actuators in five zones, each with its own Stellaz thermostat. Above it all is a Horstmann controller for the boiler. There are other remotely controllable actuators out there, and it seems sounder to me than applying/removing 120VAC to Taco pumps. At the very least, do a lot of research on what you’re trying to do before you get too far down the path. Best of luck!
watou
There are two issues with your plan as I see it. The first is obvious. You can use the sensors and Vera to energize the circulators but you also need a way to fire your boiler. This is why people use thermostats and zone controllers. The second is that these devices (Z-Wave temp/motion sensors, Vera itself, etc.) aren’t really that reliable.
Why not just get a three zone controller (or 4 if you are also heating an indirect DHW tank) and two more thermostats?
You could do this all with Z-Wave control …
You have to control 3 Pumps + the Boiler.
You can also do an even better job if you were able to measure boiler temperature and control it separately.
It would be more energy efficient to change the boiler temperature as a function of Outside temperature and if any zone is calling for heat.
Large energy savings are had in commercial environments by controlling the hot water temperature.
Without that you turn the boiler on an it try’s to maintain it’s setpoint.
You will save have some energy saving by turning off the boiler if none of the zones are calling for heat.
You can do pretty nice control using the PLEG program to control this. Many folks use this to control the Z-Wave Hot Water Zone Valve/thermostats combos.
The issue that some folks are concerned about is the reliability/response time (update speed) of the Z-Wave multi-sensors.
Actually the temperature measurement has been the most reliable sensor for my multi-sensors.
The motion is use-less … and I never found a need for the light sensor.
Z-Wave and Wifi connected thermostats will provide much better reliability for reading temperature … but if you use real thermostats … you should use the zone controller to turn on the boiler.
You might also check your zone pumps to see if they have a switch that can be used to turn on the boiler … If you have them all three can be wired in parallel to drive the boiler automatically if a zone is engaged.
How would the boiler temp be controlled this way? I’m not aware of any way to do this aside from the built in controls that monitor outside temp and so on, like are found on the newer condensing units. Buderus, Rinnai, Etc. Also how would the signal be sent to the boiler to fire?
You can get outside temperature quite reliably with Weather Underground Plugin (assuming your internet is reliable).
You would really need to install a temperature probe into the boiler (or assuming the boiler is only engaged when one pump is on … then a thermostat on the header for the circulation pumps.
The latter could be done with an Arduino Sensor:
http://forum.micasaverde.com/index.php/topic,24169.0.html
In this case the existing Boiler Temperature control would not act as a Boiler Limit control … (Max Temperature).