A:AnswerThe Ecobee can control a humidifier or one additional assessor as long as it is controlled by just a two wire system. The Ecobee does measure humidity in the main unit (not the remote sensors though).
I haven't installed mine as the wiring in not easily accessible in the wall (easily).
A:Answeryes it does. They supply a connector to take care of this. It's something you have to add in at the furnace, but it's easy to do as long as you have access to the furnace. It's a connector that terminates 5 wires to the furnace with the 4 wires one has.
A:AnswerTwo zone heating means two thermostats, with each thermostat controlling their specific zone. An obvious example, one zone for first floor, one zone for second floor. A thermostat will be located on each floor to accurately measure temperature for that zone. Most importantly, when that zone falls below or goes above the temperature threshold, it *powers on* the heating/cooling system and tells the system where to bring the heat/cooling. So, if the second floor needs more heat, the air ducts or hydronic baseboards on the second floor will open up and bring in heat, while nothing happens on the first floor.
While I'm not intimately familiar with how the remote sensor works in tandem with the thermostat's sensor, an obvious possibility is that they average their temperature readings and call for heat/cooling so that the temperature hits the set threshold in both locations. However, if you place remote sensors in a different zone, I don't think you'll ever get the cost savings or full benefits of a more balanced temperature since all you'll end up doing is running the wrong zone all the time. Following the example again, if you place a remote sensor on the second floor, with your main thermostat on your first floor, when the second floor requires heat/cooling, the equipment for the first floor turns on, rather than the second floor. You will very slowly, if ever, get the heat/cooling to float up to the second floor....
If your current thermostats are "badly placed" I think you should consider placing the new thermostats in a better location to start with, since the thermostat measures temperature from where it is physically located. So if it's located on an external wall, or in sunlight, those things will affect measurements, causing your system to turn on more frequently because the thermostat is being tricked.
For each zone, relocate your thermostat location, then choose a good location for the remote sensor, and I think you will solve your issues.
A:AnswerAll thermostats have a "swing" in temp. The anticpator built into the thermostats will have a 2-3 degree (plus or minus depending on the mode it is in) swing to prevent the a/c or heat from short cycling. The Ecobee3 is the same. If I set it to 75 in a/c mode, it will allow the temp to raise to 77 before the a/c comes on and will cool it down to 73-74 before turning off. This prevents short cycling of the system.
A:AnswerYou're right; it would deliver to the entire house, but you can use the sensor(s) to make sure it turns on/off based on the temperature in specific rooms.
A:AnswerThe Ecobee3 (like any thermostat) can only turn the A/C on or off. You could set up Ecobee sensors in your bedroom or living room and tell the system to stay on until the room of your choice hits your desired temperature.
A:AnswerIt can't regulate airflow directly. There are several features my HVAC system doesn't have (such as automatic damper positioning or a secondary fan to boost airflow to the upper levels), so I can't speak personally about things like that. However, I don't think those features are very common for household HVAC installations. It's possible that is what the accessory controls in the thermostat are there for, but I don't know and I wouldn't want to mislead you. But whether the thermostat can control things like that or not, without them there is no way to redirect airflow from one room to another.
What the thermostat does in most situations is have the system run until the weighted average of the temperature on each sensor reaches the programmed comfort level. This means that some parts of the house will be hotter or colder. For example, I have my remote sensor in the bedroom. During the "Sleep" schedule, that sensor is the only one that's enabled. The thermostat is set for 76. The bedroom is 76, but the first floor is 73-74. If I had two sensors enabled, let's say the master bedroom and a child's bedroom, then the system would average the two sensors' temperatures. So the child's bedroom might be 77 and the master might be 75. The difference is largely going to be up to your home's characteristics, how many sensors you have, which ones are active for the current comfort profile, and whether or not they read occupancy in their rooms.
