Thermostat heating/cooling


#1

Does anyone know if there is a smartapp that automatically switches between heating/cooling. I have my temp set to 73 degrees. On hot days, when set to Heating, the temp will skyrocket. Conversely, on cold days when set to Cooling, the temp will drop to eskimo. I would like to have it automatically changeover to maintain 73 degrees +/- a few degrees. I have a Honeywell 9000 I am using with Smartthings.


(Bryan) #2

Presuming your thermostat is supported, you could do that in webCore pretty easily.

You would use reaching a temperature as a trigger, Then change the mode to heating or cooling and set the temperature.


#3

I will give it a shot. Thanks!!!


#4

Do you think this looks good in order to maintain a constant 74 degree temperature? I also have a piston for going the other direction as well.


(Steve Jackson) #5

Others will chime in too but I think your “deadband” is too tight and you will see a lot if oscillation between heat & cool trying to maintain 74 degrees exactly.

My Honeywell 9580 WiFi thermostat, which automatically switches between A/C and Heat depending on the need, has a minimum 3 degree spread between the heat setpoint and cool setpoint. I.E. If A/C is 76 then my heat has to be 73 or less. My son-in-law, who has a degree in HVAC, told me that the difference between heat/cool should be 2 degrees minimum. YMMV


#6

My Honeywell also has a 3 degree spread, but for some reason it does not changeover from Heating to Cooling (in Auto Mode) which is why I am trying to get it set in Webcore. Maybe I have something set wrong. If you have any suggestions, I am definitely open to all ideas.


(Steve Jackson) #7

You probably already tried this but have you done a hard reset on the thermostat? Auto mode is the best thing. I loved it in Michigan where you use the A/C and heat quite often in the same day. Here in Florida it happens too just not very often.

If you can’t get auto to work I would think you could use a webcore piston. Couldn’t you set the heat setpoint and the cool setpoint on the thermostat and change the thermostat mode from heat to cool without having to adjust the setpoint using webcore. If you adjust the setpoint in webcore keep in mind that it will trigger and “permanent hold” on the thermostat.


(Steve Jackson) #8

Here is what the face of my Honeywell looks like in Auto Mode.


#9

My face looks like this too. I think we have the same thermostat.


(Steve Jackson) #10

It sounds like it. I know in preference you can do a “restore to factory defaults” but I am not sure what that does without getting out my book. I’m sure there is a way to do a reset and start over. I think that something is mucked up in the thermostat.

Did AUTO ever work?


(Bryan) #11

So if the temp drops below 74, then it will switch to heat (probably from auto) and set the setpoint to 74, which it probably already is. The reason I say those things probably are is because they will have been set in your else statement. Not sure I follow the logic.

I agree with @oldcomputerwhiz. I think you need to trigger the mode to heat at or below 73 and trigger the mode to AC at or above 75. I think you just need two IF statements and no ELSE statements.

I think you can also just leave the setpoint constant. I mentioned programming it in my first post because I have different setpoints for heating and cooling.


#12

Cant recall if it ever worked. I just kind of dealt with it. I may try a reset after I get back from the boy’s baseball practice. Can’t hurt


#13

Alright, I will try that as well.


(Steve Jackson) #14

You probably are better than me but just make sure that you remember how to set up your equipment. I struggled with that a bit when I came from a forced air gas system in Michigan to a package system with electric heat in Florida. I got it working but couldn’t do it again from memory if my life depended on it. :thinking:

Hopefully a reset will give you auto mode. Otherwise, if it doesn’t, a webcore piston should work. If it were me, and I had to use the piston, I would use the thermostat programming to set my A/C & heating setpoints and then use the piston to trigger the mode based on the setpoints in the thermostat.

Good luck!!


(Sully) #15

Just to give you an idea. Here’s mine. There’s more to it, but I like mine to stay at 70, but I don’t really notice it if it varies by about two degrees. If mine gets to 68 or below, it switches to heat, and sets the setpoint correctly. If it gets to 72, it switches to cool and adjusts the setpoint. And just in case I do notice a difference, I have two momentary tile buttons, Heat and Cool, and I can tell Alexa to turn them on, and it does it for me.

Stasis is part of the Energy saving stuff I do. It sets to the wider setpoints when I’m away to keep the HVAC from running too much, but this is the basics of what you were looking for. Hope that helps!


#16

Wow, that is a complicated one…lol. I don’t even know where to start with it. Thanks. I think I will give Honeywell a call and see what they can do for me then I will go from there.


(Steve Jackson) #17

I take it a reset didn’t work?

I’m waiting to see if/how you fix the “AUTO” issue in case it happens to my thermo.


#18

Reset didn’t work. I’m going to just monitor it at this point. Basically, I have everything in AUTO mode Heat set to 74 degrees and Cool set to 77 degrees. Ideally, I would like the temp to stay around 74 degrees. Now what usually happens is if its a hot day the temp will go up to 80 degrees or so. In this case I would have to change the cool to 74 degrees to get it to cool back down. This is where I am getting confused because I thought AUTO mode keeps the temp within the range I set plus or minus a few degrees.


(Steve Jackson) #19

Something isn’t right. Based on your setpoints, if the temp in the house hits 78, then the A/C should turn on and bring the temp to 77 (your A/C setpoint). If the temp in the house should drop to 73, then the heat would turn on and bring the temp to 74 (your heat setpoint).

With those setpoints in Auto mode the house should never hit 80 degrees.


#20

That’s what I mean. Something is not kicking in when it’s supposed to. Same thing happens when the temperature goes in the cooler direction.