I have owned a CB1200i for a little less than a year but the Skytech II Inc. branded "Smart Stat II" thermostat died about two weeks ago. I decided to upgrade to an Ecobee3 Lite smart thermostat as we have two, one for our upstairs HVAC and one for downstairs. I was actually able to get an Ecobee 4 for $99 after all discounts so I swapped that one for our upstairs unit and put the Ecobee3 Lite downstairs for the pellet stove.
I used the following for the upgrade:
1) ELK brand ELK-TRG2440 24 volt AC, 40 VA transformer from Grainger Industrial
2) 18/2 thermostat wire from Home Depot
3) Ecobee3 lite thermostat from Home Depot (BGE has a $100 instant rebate on them when purchased through Home Depot)
4) Standard 15A 5-15R outlet (mine are all Luton Decora rectangular style outlets without a screw in the middle and the transformer uses a screw to the middle of the outlet to keep it in place because it is a bit heavy)
Wiring - I ran two lengths of 18/2 thermostat wire from the thermostat to the pellet stove, one for power and one for pellet stove control. I did this because I wanted the transformer and the pellet stove to plug into the same outlet since this outlet is backed up by a standby generator. It also makes it easy to completely remove power from the thermostat and pellet stove if necessary.
Power - Since the thermostat runs on 24v power I needed the 24v transformer to power it. I wanted it to be accessible so I opted for an ELK transformer that plugs into a standard 5-15R outlet. It has three screw terminals in the back and these go to the Rc and C terminals on the thermostat. Ecobee has a nice wiring diagram here and the pellet stove uses RW contacts:
https://support.ecobee.com/hc/en-us...-furnace-installations-for-ecobee-thermostats
The middle ground terminal is not used. The outside two terminals are used and it doesn't matter which one is wired to Rc and C. When plugged in, the transformer has an included screw to keep it plugged in as it is a bit heavy. It also makes a slight humming sound like other transformers do.
Pellet Stove Control - I wired up the other 18/2 thermostat wire run from the pellet stove control contacts to the Rh and W1 terminals of the thermostat (from the wiring diagram above.) I noted that it did not matter which one was wired to Rh and W1.
Ecobee3 LIte settings - When I finished wiring, I plugged in the pellet stove power. Then I plugged in the Ecobee3 Lite thermostat into the Ecobee base on the wall. It powered up and then started an installation wizard. Once the wizard was complete I had control of the pellet stove from the Ecobee3 lite. I also use an Amazon Alexa and so I labeled the thermostat "Pellet Stove" so I can start it, stop it, or change temperature by just using "Pellet Stove" with Alexa.
With the old Skytech thermostat it would run the pellet stove until it was +2 degrees F above set temperature. It would then come on again at -2 degrees F below the set temperature. For the Ecobee3 Lite the default is to stop at set temperature and to turn on again at -0.5 degrees F below set temperature. I adjusted that to be the max heat temperature differential, which is -3 degrees F below set temperature. I have the set temperature +1 degree above my old setting so it is almost the same heating activity.
To prevent short cycling I also set the heat min on time to 15 minutes, but I may set that longer. Right now I don't have any problems with short cycling since it has been fairly cold out.
The settings I have set are as follows:
Settings - Equipment
- Boiler
- Wiring - Rc, Rh, C, W1
Settings - Installation Settings - Thresholds
- Heat Differential Temperature: 3.0 degrees F (max setting)
- Heat Min On time: 15 min
Settings - Preferences
- Thermostat Name: Pellet Stove
Preferences
- Hold Action: Until Next Activity (If you manually set a temperature it stays on that until the next scheduled temperature change.)
Preferences
- Heating Smart Recovery: Enable (will figure out how long it takes to reach your scheduled temperature at a schedule change time and start the heat so that it reaches that heat at your desired time. Like if you say 72 degrees F at 07:00 it might start it at 06:45 to get the temp to 72 by 07:00)
I used the following for the upgrade:
1) ELK brand ELK-TRG2440 24 volt AC, 40 VA transformer from Grainger Industrial
2) 18/2 thermostat wire from Home Depot
3) Ecobee3 lite thermostat from Home Depot (BGE has a $100 instant rebate on them when purchased through Home Depot)
4) Standard 15A 5-15R outlet (mine are all Luton Decora rectangular style outlets without a screw in the middle and the transformer uses a screw to the middle of the outlet to keep it in place because it is a bit heavy)
Wiring - I ran two lengths of 18/2 thermostat wire from the thermostat to the pellet stove, one for power and one for pellet stove control. I did this because I wanted the transformer and the pellet stove to plug into the same outlet since this outlet is backed up by a standby generator. It also makes it easy to completely remove power from the thermostat and pellet stove if necessary.
Power - Since the thermostat runs on 24v power I needed the 24v transformer to power it. I wanted it to be accessible so I opted for an ELK transformer that plugs into a standard 5-15R outlet. It has three screw terminals in the back and these go to the Rc and C terminals on the thermostat. Ecobee has a nice wiring diagram here and the pellet stove uses RW contacts:
https://support.ecobee.com/hc/en-us...-furnace-installations-for-ecobee-thermostats
The middle ground terminal is not used. The outside two terminals are used and it doesn't matter which one is wired to Rc and C. When plugged in, the transformer has an included screw to keep it plugged in as it is a bit heavy. It also makes a slight humming sound like other transformers do.
Pellet Stove Control - I wired up the other 18/2 thermostat wire run from the pellet stove control contacts to the Rh and W1 terminals of the thermostat (from the wiring diagram above.) I noted that it did not matter which one was wired to Rh and W1.
Ecobee3 LIte settings - When I finished wiring, I plugged in the pellet stove power. Then I plugged in the Ecobee3 Lite thermostat into the Ecobee base on the wall. It powered up and then started an installation wizard. Once the wizard was complete I had control of the pellet stove from the Ecobee3 lite. I also use an Amazon Alexa and so I labeled the thermostat "Pellet Stove" so I can start it, stop it, or change temperature by just using "Pellet Stove" with Alexa.
With the old Skytech thermostat it would run the pellet stove until it was +2 degrees F above set temperature. It would then come on again at -2 degrees F below the set temperature. For the Ecobee3 Lite the default is to stop at set temperature and to turn on again at -0.5 degrees F below set temperature. I adjusted that to be the max heat temperature differential, which is -3 degrees F below set temperature. I have the set temperature +1 degree above my old setting so it is almost the same heating activity.
To prevent short cycling I also set the heat min on time to 15 minutes, but I may set that longer. Right now I don't have any problems with short cycling since it has been fairly cold out.
The settings I have set are as follows:
Settings - Equipment
- Boiler
- Wiring - Rc, Rh, C, W1
Settings - Installation Settings - Thresholds
- Heat Differential Temperature: 3.0 degrees F (max setting)
- Heat Min On time: 15 min
Settings - Preferences
- Thermostat Name: Pellet Stove
Preferences
- Hold Action: Until Next Activity (If you manually set a temperature it stays on that until the next scheduled temperature change.)
Preferences
- Heating Smart Recovery: Enable (will figure out how long it takes to reach your scheduled temperature at a schedule change time and start the heat so that it reaches that heat at your desired time. Like if you say 72 degrees F at 07:00 it might start it at 06:45 to get the temp to 72 by 07:00)