Mass Saves thermostat program

[BostonMike7]

When you remote into the device, go to settings -> technical info and scroll down to the battery voltage and keep an eye on this. Full charge is 3.9 volts. I believe when you get down to 3.7 volts, the wifi turns off to conserve battery power. Take a peek during the period when the heat is on for a long period when warming up an area for the day. If you find the battery is draining down too low during this time, you may want to add a C wire.

[jayrandom]

Originally Posted by BostonMike7

I agree.


But my thinking is that if it takes ~ 1 hr to heat that room up from 55 degrees to 68 degrees, I could make use of the other times the furnace is active during the day to piggy-back on that demand and run the circulator for that particular room only if the main level is active. That way, when it comes time to use the room, we might be talking about bumping it from 63 degrees to 68 degrees which will use less energy.


Of course I realize adding that zone when the main runs will require additional energy due to more water being heated and radiated. Really a case of figuring out which way using more energy. It's tricky to try and figure that out because Nest only registers the time the thermostat is active. When I heat that single zone, I hit the 180* temp limit pretty quick so the circulator keeps pumping but the heater isn't actually on. So while it might take 1 hr to heat the room up, the heat might only be on for 30 mins. When the main level zone comes on, i'll never hit the 180* limit so the room will heat up MUCH faster if done so with the main level on and the heater constantly on. The nest doesn't really log this info correctly so I can't use it to decide best efficiency.

I agree that it could be done with some programming logic and an arduino controlling the various circulators.


Main on -> If zone 2 less than X degrees, turn on zone 2. If zone 2 > x degrees, leave zone 2 off.

Newton's law of cooling is a reasonable place to start, and there heat lost is proportional to the temperature difference. You would have to have a really strangely inefficient system to use more energy to heat a room all the time than to let the room cool, even though you do use more power when you want the room hot. This is Massachusetts so I wouldn't say that's impossible, but you're definitely dumping more heat outside when you keep the room warm. I have what seems a similar situation to you (room over the garage on its own zone) and we keep it as cold as feasible when we aren't using it.

Now that I think about it, you might be able to use IFTTT (if this, then that) to connect multiple nests together using a smart home hub.

[BostonMike7]

Originally Posted by jayrandom

Now that I think about it, you might be able to use IFTTT (if this, then that) to connect multiple nests together using a smart home hub.

But id need a way for the NEST's to transmit temp info to the controller to allow it to make decisions. All the controller will really see is the call for heat from each tstat. I was raking my brain over this last night.

[GeePee]

Originally Posted by BostonMike7

When you remote into the device, go to settings -> technical info and scroll down to the battery voltage and keep an eye on this. Full charge is 3.9 volts. I believe when you get down to 3.7 volts, the wifi turns off to conserve battery power. Take a peek during the period when the heat is on for a long period when warming up an area for the day. If you find the battery is draining down too low during this time, you may want to add a C wire.

Thats great info. Thanks. I had the heat on from 4:30 to 6:30 this am and it has been in eco mode since I put it there. The Battery is reading 3.89 currently. I will monitor throughout the day.

[GeePee]

Guys. Since I have posted this the prices on the Mass saves site have been severely chopped. (stinks for me)
Currently the Nest is $99 and you can get 2 Nest E for $58 which is insane. I wish I waited

[BostonMike7]

I need to look into this. The kiddos were playing a little soccer in the basement and took my the one I had down there. Dislodged the unit and it fell onto a hard tile floor and bent it slightly. Difficult to rotate.


I can probably ebay it and get a new one for about the same.

[MikePRU]

Originally Posted by GeePee

Guys. Since I have posted this the prices on the Mass saves site have been severely chopped. (stinks for me)
Currently the Nest is $99 and you can get 2 Nest E for $58 which is insane. I wish I waited

Do you have to log in to see the pricing?

[GeePee]

Yes