# Esp8266 inaccurate temp reading

**URL:** <https://community.smartthings.com/t/esp8266-inaccurate-temp-reading/152641>\
**Category:** Connected Things\
**Tags:** esp8266\
**Created:** [February 3, 2019, 1:47pm UTC](https://community.smartthings.com/t/esp8266-inaccurate-temp-reading/152641 "2019-02-03T13:47:24Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![LL\_Tool\_J](https://avatars.discourse-cdn.com/v4/letter/l/ecb155/32.png) [@LL\_Tool\_J](https://community.smartthings.com/u/LL_Tool_J)\
**Post date:** [February 3, 2019, 1:47pm UTC](https://community.smartthings.com/t/esp8266-inaccurate-temp-reading/152641/1 "2019-02-03T13:47:24Z")

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I’ve connected a NodeMCU esp8266 to my ST hub (many thanks @ogiewon!) and added it as a device on my ST iOS app. The two thermostats are showing a temperature of -196.6. Any suggestions on how I can adjust the base reading so it matches up with the correct temperature? Thanks for the help.

M

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**Author:** ![ogiewon](https://yyz2.discourse-cdn.com/smartthings/user_avatar/community.smartthings.com/ogiewon/32/13743_2.png) [@ogiewon](https://community.smartthings.com/u/ogiewon)\
**Post date:** [February 3, 2019, 1:52pm UTC](https://community.smartthings.com/t/esp8266-inaccurate-temp-reading/152641/2 "2019-02-03T13:52:03Z")

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> [@LL\_Tool\_J](#):
>
> The two thermostats are showing a temperature of -196.6.

If you’re reading -196.6, I believe you may have a wiring problem with your sensors. What type of sensors are you using? Can you share a picture or diagram of how you have things wired? Also, if you can share your Arduino sketch, that would help to diagnose the problem as well.

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**Author:** ![Oldjetdriver](https://avatars.discourse-cdn.com/v4/letter/o/0ea827/32.png) [@Oldjetdriver](https://community.smartthings.com/u/Oldjetdriver)\
**Post date:** [February 4, 2019, 1:10pm UTC](https://community.smartthings.com/t/esp8266-inaccurate-temp-reading/152641/3 "2019-02-04T13:10:43Z")

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If you are using a DS18B20 temp sensor it requires wiring a 4.7K Ohm resistor connecting the + to data.

 ![Nodemcu%20and%20DC18B20](https://global.discourse-cdn.com/smartthings/original/3X/d/b/dbb70e92971579542e44b69ac042848fea302e75.jpeg)

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**Author:** ![Nishal\_Shah](https://yyz2.discourse-cdn.com/smartthings/user_avatar/community.smartthings.com/nishal_shah/32/148437_2.png) [@Nishal\_Shah](https://community.smartthings.com/u/Nishal_Shah)\
**Post date:** [December 5, 2022, 10:01am UTC](https://community.smartthings.com/t/esp8266-inaccurate-temp-reading/152641/4 "2022-12-05T10:01:37Z")

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@ogiewon @Oldjetdriver I am facing the same issue can you help.

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**Author:** ![ogiewon](https://yyz2.discourse-cdn.com/smartthings/user_avatar/community.smartthings.com/ogiewon/32/13743_2.png) [@ogiewon](https://community.smartthings.com/u/ogiewon)\
**Post date:** [December 5, 2022, 1:59pm UTC](https://community.smartthings.com/t/esp8266-inaccurate-temp-reading/152641/5 "2022-12-05T13:59:55Z")

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Same advice above applies. I am no longer supporting ST\_Anything on the SmartThings platform as Groovy is going away at the end of this month.