diff --git a/interface/src/mqtt/MqttSettingsForm.tsx b/interface/src/mqtt/MqttSettingsForm.tsx
index 7a865d930..899781d1f 100644
--- a/interface/src/mqtt/MqttSettingsForm.tsx
+++ b/interface/src/mqtt/MqttSettingsForm.tsx
@@ -158,9 +158,10 @@ class MqttSettingsForm extends React.Component<MqttSettingsFormProps> {
           variant="outlined"
           onChange={handleValueChange('bool_format')}
           margin="normal">
-          <MenuItem value={1}>on/off</MenuItem>
+          <MenuItem value={1}>"on"/"off"</MenuItem>
           <MenuItem value={2}>true/false</MenuItem>
           <MenuItem value={3}>1/0</MenuItem>
+          <MenuItem value={4}>"ON"/"OFF"</MenuItem>
         </SelectValidator>
         <BlockFormControlLabel
           control={
diff --git a/src/helpers.cpp b/src/helpers.cpp
index 0c7e27a2d..63d9e6b26 100644
--- a/src/helpers.cpp
+++ b/src/helpers.cpp
@@ -127,6 +127,8 @@ char * Helpers::render_boolean(char * result, bool value) {
     uint8_t bool_format_ = Mqtt::bool_format();
     if (bool_format_ == BOOL_FORMAT_ONOFF) {
         strlcpy(result, value ? "on" : "off", 5);
+    } else if (bool_format_ == BOOL_FORMAT_ONOFF_CAP) {
+        strlcpy(result, value ? "ON" : "OFF", 5);
     } else if (bool_format_ == BOOL_FORMAT_TRUEFALSE) {
         strlcpy(result, value ? "true" : "false", 7);
     } else {
diff --git a/src/locale_EN.h b/src/locale_EN.h
index de89d0062..7e3dd9b9c 100644
--- a/src/locale_EN.h
+++ b/src/locale_EN.h
@@ -30,6 +30,8 @@ MAKE_PSTR_WORD(set)
 MAKE_PSTR_WORD(show)
 MAKE_PSTR_WORD(on)
 MAKE_PSTR_WORD(off)
+MAKE_PSTR_WORD(ON)
+MAKE_PSTR_WORD(OFF)
 MAKE_PSTR_WORD(su)
 MAKE_PSTR_WORD(name)
 MAKE_PSTR_WORD(auto)
@@ -211,16 +213,7 @@ MAKE_PSTR_WORD(holiday)
 MAKE_PSTR_WORD(reduce)
 
 // thermostat lists
-MAKE_PSTR_LIST(enum_ibaMainDisplay,
-               F_(internal_temperature),
-               F_(internal_setpoint),
-               F_(external_temperature),
-               F_(burner_temperature),
-               F_(WW_temperature),
-               F_(functioning_mode),
-               F_(time),
-               F_(date),
-               F_(smoke_temperature))
+MAKE_PSTR_LIST(enum_ibaMainDisplay, F_(internal_temperature), F_(internal_setpoint), F_(external_temperature), F_(burner_temperature), F_(WW_temperature), F_(functioning_mode), F_(time), F_(date), F_(smoke_temperature))
 MAKE_PSTR_LIST(enum_ibaLanguage, F_(German), F_(Dutch), F_(French), F_(Italian))
 MAKE_PSTR_LIST(enum_floordrystatus, F_(off), F_(start), F_(heat), F_(hold), F_(cool), F_(end))
 MAKE_PSTR_LIST(enum_ibaBuildingType, F_(blank), F_(light), F_(medium), F_(heavy))
diff --git a/src/mqtt.h b/src/mqtt.h
index f120a8ecc..fd2231384 100644
--- a/src/mqtt.h
+++ b/src/mqtt.h
@@ -44,7 +44,7 @@ using uuid::console::Shell;
 // size of queue
 #define MAX_MQTT_MESSAGES 100
 
-enum { BOOL_FORMAT_ONOFF = 1, BOOL_FORMAT_TRUEFALSE, BOOL_FORMAT_10 }; // matches Web UI settings
+enum { BOOL_FORMAT_ONOFF = 1, BOOL_FORMAT_TRUEFALSE, BOOL_FORMAT_10, BOOL_FORMAT_ONOFF_CAP }; // matches Web UI settings
 
 namespace emsesp {