# CT100 Plus - Temperature Settings Shifting

**URL:** <https://community.smartthings.com/t/ct100-plus-temperature-settings-shifting/293599>\
**Category:** Devices & Integrations\
**Created:** [January 13, 2025, 1:31pm UTC](https://community.smartthings.com/t/ct100-plus-temperature-settings-shifting/293599 "2025-01-13T13:31:26Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![jeff1](https://yyz2.discourse-cdn.com/smartthings/user_avatar/community.smartthings.com/jeff1/32/218484_2.png) [@jeff1](https://community.smartthings.com/u/jeff1)\
**Post date:** [January 13, 2025, 1:31pm UTC](https://community.smartthings.com/t/ct100-plus-temperature-settings-shifting/293599/1 "2025-01-13T13:31:26Z")

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**tl;dr - I’ve been using CT100 and CT100 Plus thermostats for years. Starting a few weeks ago I started seeing my heat temperature settings shifting up by .2 to .5 degrees. I set the heat setpoint to 65, and it changes fine. Then within a few seconds it shifts to 65.2. Or 65.5**. I have 4 of these thermostats across two different hubs, and they all started doing this recently.

Why does that matter? Because these thermostats kick in emergency heat + stage 2 heating after a \> 2 temperature differential of actual vs setpoint. I have a number of routines to gradually heat my homes before I arrive, using only the heat pump (takes hours but saves $$). Those routines break when that extra increase in the setpoint triggers the heating strips. e.g. the 10k heating strips fire up immediately.

I HATE it when devices that work for years suddenly stop working ☹ . Any insights would be appreciated.

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**Author:** ![h0ckeysk8er](https://yyz2.discourse-cdn.com/smartthings/user_avatar/community.smartthings.com/h0ckeysk8er/32/195141_2.png) [@h0ckeysk8er](https://community.smartthings.com/u/h0ckeysk8er)\
**Post date:** [January 13, 2025, 4:05pm UTC](https://community.smartthings.com/t/ct100-plus-temperature-settings-shifting/293599/2 "2025-01-13T16:05:14Z")

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> [@jeff1](#):
>
> **tl;dr - I’ve been using CT100 and CT100 Plus thermostats for years. Starting a few weeks ago I started seeing my heat temperature settings shifting up by .2 to .5 degrees. I set the heat setpoint to 65, and it changes fine. Then within a few seconds it shifts to 65.2. Or 65.5**. I have 4 of these thermostats across two different hubs, and they all started doing this recently.
> 
> Why does that matter? Because these thermostats kick in emergency heat + stage 2 heating after a \> 2 temperature differential of actual vs setpoint. I have a number of routines to gradually heat my homes before I arrive, using only the heat pump (takes hours but saves $$). Those routines break when that extra increase in the setpoint triggers the heating strips. e.g. the 10k heating strips fire up immediately.
> 
> I HATE it when devices that work for years suddenly stop working ☹ . Any insights would be appreciated.

See this post.

> [@Heating Set Point off by 0.2°F](https://community.smartthings.com/t/heating-set-point-off-by-0-2-f/293106/5):
>
> Since the latest updates to the iOS and Android Apps, the introduction of the thermostatHeatingSetpoint and thermostatCoolingSetpoint capabilities does not allow temperature changes other than multiples of the interval (step) defined in the profile, by default 1°, starting at the lower temperature limit defined in the profile. Before it did allow it. The problem is that the temperature range is in °C and when it is converted to °F it will normally have decimals. For location in °C there’s not decimals problem The base-thermostat profile of the zwave driver has a range of 4°c to 28°c. Others profiles can have different range which in °F is 39.2°F to 82.4°F. - id: thermostatHeatingSetpoint version: 1 config: values: - key: "heatingSetpoint.value" range: [4, 28] On this profile, the a…