diff --git a/mqtt/src/main/java/dev/cookiecode/rika2mqtt/rika/mqtt/configuration/MqttConfiguration.java b/mqtt/src/main/java/dev/cookiecode/rika2mqtt/rika/mqtt/configuration/MqttConfiguration.java
index fee74e8..4cb2d34 100644
--- a/mqtt/src/main/java/dev/cookiecode/rika2mqtt/rika/mqtt/configuration/MqttConfiguration.java
+++ b/mqtt/src/main/java/dev/cookiecode/rika2mqtt/rika/mqtt/configuration/MqttConfiguration.java
@@ -59,6 +59,8 @@
 @Flogger
 public class MqttConfiguration {
 
+  private static final String DELIMITER = ":";
+  private static final String STOVE_ID = "stoveId";
   private final MqttConfigProperties mqttConfigProperties;
   private final ApplicationEventPublisher applicationEventPublisher;
   private final Gson gson;
@@ -71,7 +73,7 @@ public MqttPahoClientFactory mqttClientFactory() {
         new String[] {
           mqttConfigProperties.getUriScheme()
               + mqttConfigProperties.getHost()
-              + ":"
+              + DELIMITER
               + mqttConfigProperties.getPort()
         });
     options.setUserName(mqttConfigProperties.getUsername());
@@ -159,10 +161,10 @@ public MessageHandler mqttInputMessageHandler() {
       try {
         final var type = new TypeToken<Map<String, String>>() {}.getType();
         final Map<String, String> props = gson.fromJson(payload, type);
-        final var stoveId = Long.parseUnsignedLong(props.get("stoveId"));
+        final var stoveId = Long.parseUnsignedLong(props.get(STOVE_ID));
 
         // remove stoveId props as it has its own property in the wrapping object
-        props.remove("stoveId");
+        props.remove(STOVE_ID);
 
         applicationEventPublisher.publishEvent(
             MqttCommandEvent.builder().withStoveId(stoveId).withProps(props));