diff --git a/src/devices/heatpump.cpp b/src/devices/heatpump.cpp
index 463a4cd7d..195d0da97 100644
--- a/src/devices/heatpump.cpp
+++ b/src/devices/heatpump.cpp
@@ -97,7 +97,7 @@ void Heatpump::register_mqtt_ha_config() {
     }
 
     // Create the Master device
-    StaticJsonDocument<EMSESP_MAX_JSON_SIZE_SMALL> doc;
+    StaticJsonDocument<EMSESP_MAX_JSON_SIZE_HA_CONFIG> doc;
     doc["name"]    = F_(EMSESP);
     doc["uniq_id"] = F_(heatpump);
     doc["ic"]      = F_(iconheatpump);
diff --git a/src/devices/mixer.cpp b/src/devices/mixer.cpp
index c95f1a06b..db96d2c0a 100644
--- a/src/devices/mixer.cpp
+++ b/src/devices/mixer.cpp
@@ -166,7 +166,7 @@ void Mixer::register_mqtt_ha_config() {
     }
 
     // Create the Master device
-    StaticJsonDocument<EMSESP_MAX_JSON_SIZE_MEDIUM> doc;
+    StaticJsonDocument<EMSESP_MAX_JSON_SIZE_HA_CONFIG> doc;
 
     char name[20];
     snprintf_P(name, sizeof(name), PSTR("Mixer %02X"), device_id() - 0x20 + 1);
diff --git a/src/devices/solar.cpp b/src/devices/solar.cpp
index 438e179c8..c341e01c1 100644
--- a/src/devices/solar.cpp
+++ b/src/devices/solar.cpp
@@ -159,7 +159,7 @@ void Solar::register_mqtt_ha_config() {
     }
 
     // Create the Master device
-    StaticJsonDocument<EMSESP_MAX_JSON_SIZE_SMALL> doc;
+    StaticJsonDocument<EMSESP_MAX_JSON_SIZE_HA_CONFIG> doc;
     doc["name"]    = F_(EMSESP);
     doc["uniq_id"] = F_(solar);
     doc["ic"]      = F_(iconthermostat);