Docs for PR #3255

ACKNOWLEDGEMENTS.md

@@ -925,3 +925,4 @@ Further device support has been made with the assistance of users. Please consid
 - [bputtick](https://github.com/bputtick) for contributing support for ElectriQ SupremeCool SC16HPW air conditioner.
 - [EmilianoMorello](https://github.com/EmilianoMorello) for contributing support for generic PIR alarm.
 - [LordGuenni](https://github.com/LordGuenni) for contributing support for Inkbird IBS-M2 temperature probe hub.
+- [arni077r](https://github.com/arni077r) for contributing support for Euroster 4040 Smart thermostat.

DEVICES.md

@@ -187,6 +187,7 @@
 - ETOP-HT thermostat
 - ETOP-HT-CH thermostat (branded as Ferco GN1)
 - Eurom WiFi thermostat
+- Euroster 4040 Smart thermostat
 - EZAIoT R9Lite thermostat
 - EZAIoT thermostat smartplug
 - Hysen HY02TP, HY08ACF, HY08WE-2, HY101RF thermostats