Complex Heating System - Sanity check

Posted on
Tue Oct 15, 2013 5:22 am
wysinawyg offline
Posts: 45
Joined: Oct 11, 2013

Complex Heating System - Sanity check

Right I'm looking to use indigo to install approx 10 zones of principally radiator controlled heating. All of the Zones will be run automatically using Jay's plugin to schedule temperatures, some of them will also have separate wall thermostats to allow manual adjustments (or else the Wife will never go for it).

So I'm looking to have a Stella-Z on every radiator, Secure Thermostats and the double Relay Secure Boiler Actuator.

The plan:

1. Rather than just using setpoints on the radiator valves (which makes it hard to know if a radiator valve is open or closed) or looking at the actual Thermostats, I'm intending to set up each room with its own Setpoint and Current Temperature variable. The Thermostats (for the rooms that have them) will control the Setpoint variable (but the Thermostats will in turn be controlled by the indigo schedule) and report the Current Temperature variable. For rooms without thermostats the Stella-Zs will report the Current Temperature and the Setpoint will be wholly set by indigo (through schedules and later iDevice).

2. There will then be triggers set up each time a room's Setpoint or Current Temperature changes which will compare the two and flag a "Call for Heat" variable for that room if the Setpoint is higher than Current Temperature. If a room's "Call for Heat" gets flagged that will also trigger all of its radiator valves opening up (by setting the Stella-Z to 30C setpoint) with them all closing if the flag comes off (by setting to 5C).

3. There will then be another trigger to fire every time one of the room "Call for Heat" variables changes which will look at whether or not 1 or more of them is flagged and put the Boiler on if it is.

4. Finally I'll have a scheduled test of the Boiler trigger every 30 minutes as the Boiler controller is set to default off if it doesn't hear anything for an hour.

The way I figure it that means I need a little bit of Python scripting for an "if" "or" "or" "or" etc. "else" check on the "Call for Heat" variables and an "if" "else" for the rooms themselves to set that variable.

Does that sound feasible? Does it sound like too many calls on indigo if its constantly setting off scripts every time a room moves by a degree?

Presumably I'm best learning a little more about the Python scripting so that 2 all happens on a single test (if Setpoint > Temperature [flag "Call for Heat" and open radiator valves] else [unflag "Call for Heat" and close radiator valves]) rather than if I run a separate trigger to open or close the valves based on the "Call for Heat" changing?

Cheers all for any thoughts.

Posted on
Tue Oct 15, 2013 8:40 am
autolog offline
Posts: 3988
Joined: Sep 10, 2013
Location: West Sussex, UK [GMT aka UTC]

Re: Complex Heating System - Sanity check

The Python script I am working on probably does 90%+ of what you want to do. I have just got to tidy a few things up and then you are welcome to it (to use/modify as you see fit). I have described it in this post. :)

btw - Which plugin (Jay's) are you referring to?

Posted on
Wed Oct 16, 2013 4:51 am
wysinawyg offline
Posts: 45
Joined: Oct 11, 2013

Re: Complex Heating System - Sanity check

Sorry just an Applescript rather than a plugin but I mean this one:

http://www.perceptiveautomation.com/wik ... ced_thermo

As I read it I should be able to get a pretty much infinite number of heating schedules put in so I can, for example, bump the heat in the nursery up for naps for a couple of hours at a time, pop the heating on in the office for the two days a week my wife works etc. But also allow manual override where I want it with room thermostats (though I need to think about how long I want to allow the overrides and how to control that).

I reckon to do that I need to separate out the Setpoint setting from the Boiler activation, but I was planning to plunder your work once it goes up :twisted: as well as feeding off some of the responses you've had along the way :D

Page 1 of 1

Who is online

Users browsing this forum: No registered users and 4 guests

cron