diff --git a/src/devices/thermostat.cpp b/src/devices/thermostat.cpp
index 585d0717c..5f3f6f144 100644
--- a/src/devices/thermostat.cpp
+++ b/src/devices/thermostat.cpp
@@ -3846,18 +3846,9 @@ void Thermostat::register_device_values() {
                               MAKE_CF_CB(set_wwVacation));
         break;
     case EMS_DEVICE_FLAG_JUNKERS:
-        if (has_flags(EMS_DEVICE_FLAG_JUNKERS_OLD)) {
-            // FR100 is not writable, see. https://github.com/emsesp/EMS-ESP32/issues/536
-            register_device_value(DeviceValueTAG::TAG_DEVICE_DATA, &dateTime_, DeviceValueType::STRING, FL_(tpl_datetime), FL_(dateTime), DeviceValueUOM::NONE);
-        } else {
-            register_device_value(DeviceValueTAG::TAG_DEVICE_DATA,
-                                  &dateTime_,
-                                  DeviceValueType::STRING,
-                                  FL_(tpl_datetime),
-                                  FL_(dateTime),
-                                  DeviceValueUOM::NONE,
-                                  MAKE_CF_CB(set_datetime));
-        }
+        // FR100 is not writable, see. https://github.com/emsesp/EMS-ESP32/issues/536
+        // also FW500 https://github.com/emsesp/EMS-ESP32/issues/666
+        register_device_value(DeviceValueTAG::TAG_DEVICE_DATA, &dateTime_, DeviceValueType::STRING, FL_(tpl_datetime), FL_(dateTime), DeviceValueUOM::NONE);
         register_device_value(DeviceValueTAG::TAG_DEVICE_DATA,
                               &hybridStrategy_,
                               DeviceValueType::ENUM,