I am looking for a portable thermostat to connect to my ct100 that i currently have installed upstairs. I want to take portable thermostat downstairs at night and have thermostat kick on/off depending on the temperature of my portable thermostat not upstairs temperature. Any products that would do this?
It doesn’t sound like you need a thermostat. You just need a temperature sensor. Then the temperature sensor reports the current temperature to the smartthings hub and you use an automation to then control the CT 100 based on that temperature sensor. Many people do this. And you shouldn’t need to carry it back and forth. You can just create your rule to control when you want to factor in the remote sensor and when you don’t.
There are lots of battery operated sensors that Report temperature, often it’s a secondary feature in an open/close sensor or a motion sensor. For example, the new $20 smartthings open/close sensor also reports temperature. But there are many others as well.
I like this idea but not sure how to tell the boiler to light??
Would need some sort of relay ??
You can try Ecobee thermostat with remote sensors.
Since you already have a SmartThings-controllable thermostat, the simple solution that @JDRoberts outlines would use any ST thermometer device downstairs, and it would increase the heating setpoint/decrease the cooling setpoint of the upstairs thermostat until the downstairs target setpoint was achieved.
I haven’t seen such a standalone SmartApp available for free anywhere, but it would be reasonable easy to code in either native Groovy or using WebCoRE.
The poster you replied to is talking about a water boiler based home heating system such as is commonly used in the UK. These are rather different from a US type water heater used to provide hot water for bathing.
For the UK type system, see the current discussion:
As JD said you need a simple temperature sensor and an app which will use that temperature sensor to adjust your CT thermostat.
If you have access to RBoy Apps check out these apps which can use a remote temperature sensor: