Capture an omnistat actual temperature in an elk counter?

[wmcneil]

I want to be able to set an Elk counter to the value of an omnistat actual temperature. The Elk rules appear to allow a counter to be updated only with a temperature from an ELK temperature sensor. I would prefer, of course, not to have to buy and install Elk temperature sensors, since I just bought an extensive amount of Elk and HAI hardware already.

A very ugly way around this would be to write Elk rules that are firing frequently (very minute or thereabouts) and comparing the omnistat actual temperatures to a Elk counter value, and incrementing/decrementing the counter. This is not the elegant solution one would want of course.

 

[wmcneil]

I realized there is another issue after I made my post above. Let me back up and state what I am trying to do. I have an Elk M1EZ8 and omnistat thermostats. I have a heat pump, and want to turn the heat way down when I am gone for multiple days. When I want to raise the temperature back up, I want to remotely and programatically raise the heat setpoint by 1 or 2 degrees every 20 minutes, so as to avoid auxillary heat kicking in. So for example, the current temperature is 55, I have a final target temperature of 68, and I do not want to have to keep logging in remotely every 20 minutes to increase the tempertature by 1 or 2 degrees (to avoid auxilliary heat kicking in). In order to be able to do this using Elk automation I need:

1) A way to set the thermostat desired temperature to the value of a counter. Elk does not seem to have a way to do this, as you can only set the thermostat desired temperature to a fixed value or a custom setting, and I don't see any way to modify a custom setting with the value of a counter?

2) A way to allow a counter to be updated with the actual temperature from a thermostat. (This was my original question in the posting above.) This could be worked around as I indicated above with an ugly hack, or my buying an elk temperature sensor and updating the counter from the elk temp sensor,

 

[tmbrown97]

I don't have RP in front of me to test the rules out, but I can respond to this part:

1. You're going to have to do a "whenever every xx minutes" type rule to set the value of the HAI tstat to a counter.
2. I had heat pumps for 10 years - one thing I liked about the HAI was that you could set the degree difference before Aux. heat kicked in. I set mine to 5 degrees instead of the standard 2... that helps quite a bit.

 

[wmcneil]

I don't have RP in front of me to test the rules out, but I can respond to this part:

1. You're going to have to do a "whenever every xx minutes" type rule to set the value of the HAI tstat to a counter.

Yes, this is the workaround to question 2) in my posting....Maybe it's not as "ugly" as I first thought. I don't like the idea of taking up finite hardware resources for this kind of thing, but maybe it's not too bad. I am just starting to get my automation rules going, so I have plenty of room left, for now at least.

2. I had heat pumps for 10 years - one thing I liked about the HAI was that you could set the degree difference before Aux. heat kicked in. I set mine to 5 degrees instead of the standard 2... that helps quite a bit.

Hmmm....lets explore this some more. So lets say we change the Omnistat settings to ones that force absolute minimum use of aux heat as follows:

EEC (minimum rate of heating threshold before aux heat): 0 degrees per hour (default: 5 range: 0-10)
Aux Heat Differential (delta between actual and desired temp required for aux heat): 10 degrees (default: 2 range: 1-10)
Start Delay (minimum time 1st stage must be on before aux heat activated): 255 minutes (default: 5 range: 0-255)

So I am interperting the three settings above as follows, let me know if this is not correct:
a) Failing to meet the criteria for either EEC or Differential will create a demand for aux heat, and that demand will result in
actually turning on AUX heat only if Start Delay is satisfied.

So with the settings I have chosen, EEC is off, so only a temperature differential of 10 degress can create aux heat demand.
That demand will result in AUX heat actually turning on only after the 1st stage has run for 255 minutes (4 hours 15 minutes.)
Let's say the actual temperature is 50, and the final desired temperature is 68. Let's say that the system can achieve
(worst case) a gain of 3 degrees per hour. This means that the time to get from 50 to 68 is 6 hours, and the aux heat will
kick in at the 4 hour 15 minute mark. Since the goal is that a human being only has to get involved once, we still haven't solved
the problem. Also, using the settings described above are going to make for an uncomfortable house when you are present
in it, and there is no way to programatically change those settings (At least not with the elk M1 interface.)

So for general use, I like being able to tweak the three settings above to save energy, but that still leaves problem 1) from
my original post: I need a way to update to set the thermostat desired temperature to the value of a counter.