# Help with heating rule

I know there is the thermostat schedule to handle my heating and cooling but I was inspired by @aaiyar with his rules for using external temperature sensors in his house. I eventually want to get to that point but for now I've created what I thought was a simple rule for changing the temp based on mode.

I do not see anything wrong but right now when I look at my thermostat on my dashboard it shows that it's set to heat at 74 and last night I thought it was a bit warm and when I checked the dashboard showed the thermostat was set to 76. I've checked the thermostat in HE to see if there are any other rules using it and there are none. Can anyone tell me where I've messed up?

Mine

Had to put a lag inbetween to let the thermostat respond

Looks like your setting it to a temp then adjusting it 2??

What temperature are you trying to set for each mode? I don't think you should adjust the temperature and set it.

Edit:

Personally, I would split this into two rules:

Rule 1:
Set the thermostat temperature per mode (and turn it off)

Rule 2:
Adjust the thermostat temperature based on your contact sensor (with mode dependent caps). You would do this in several steps:

1. If the contact sensor temp is < 70 (Evening, Night) or < 72 (Day, morning)
1a) Recover the thermostat temperature and put it in a variable.
1b) Add 1 to that variable
1c-i) Check if the variable is =< 70 for Evening, Night. If it is then set the temp to that variable.
1c-ii) Check if the variable is =< 72 for Day, Morning. If it is then set the temp to that variable.

ELSE

1. If the Contact sensor temperature is > 70 (N, E) or > 72 (D, M)
2a) Turn off the thermostat
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May I ask why you are not using the Thermostat Scheduler app for this ? I have been using that for some time now and I am generally happy with the approach, so I am curious if you have found anything lacking that works better in RM.

I don't use Thermostat Scheduler because my thermostat doesn't accurately sample indoor air based on its location. So I basically use rules that take advantage of 8 temperature/humidity sensors around the house to control the thermostat, while ignoring temperature readings from the thermostat itself.

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I am still working on my heating control and since I am in the cold north, I can't risk turning off the thermostat. If the hub were to crash I could come home to a very cold house. I simply manipulate the heating set points a couple of degrees higher or lower to trigger the furnace. I use temperature sensors in other parts of the home for deciding when to call for heat. If the group of temperature sensors falls to a certain level, raise the heating setpoint to a couple of degrees higher than what I want my temperature to be. When the temperature sensors hit the temperature I want, RM sets the temperature to 2 degrees below my desired temperature. That way, my furnace is always ultimately still controlled by the thermostat.

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Very good point - in addition to a cold house, burst pipes are an expensive reality. Where I live, burst pipes are unlikely, but if let humidity build up for a couple weeks while I'm gone, I'll get mold.

I have a non-automated solution for both those situations.

For those that live in cold climes, I recommend installing a heating-only mechanical thermostat at the air-handler. This should be wired in parallel to the automated thermostat.

For someone like me that lives in a veritable sauna during parts of the year, a heating/cooling mechanical thermostat can get the job done. I have mine set for cooling and 80F and stuck to the outside the air-handler.

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With the Centralite Pearl, I can set a minimum and maximum for both cooling and heating in the on thermostat settings. This is outside of the heating-cooling setpoints. If I understand, it won't let the thermostat heat or cool outside of those temperatures so if an RM rule went off the rails and set the heating to 100, it wouldn't go beyond the maximum setting at the thermostat.

That is correct. My perspective is that a mechanical thermostat just uses a bimetallic strip and is less likely to fail - perfect as a backup for someone with my degree of OCDness

Although, to be fair, the situation that I have seen electronic thermostats fail is when batteries die - in 30+ years, I've never seen the electronics fail.

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I agree about the electronics reliability. I would be and am more concerned with the mechanical failure although I do like the idea of a backup.

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