diff --git a/heater_v3.ino b/heater_v3.ino
index 95d2ac3..c8ca835 100644
--- a/heater_v3.ino
+++ b/heater_v3.ino
@@ -32,6 +32,8 @@ DHT dht(DHTPIN, DHTTYPE);
 
 // deviation from target t allowed (in degrees multiplied by 100)
 #define T_HYSTERESIS 150
+// relay cooldown temperature (after what t we allow to turn on relay again) (in degrees multiplied by 100)
+#define RELAY_COOLDOWN_T 500
 // timeout to switch from external to internal temperature data (in milliseconds)
 #define SWITCH_TO_INTERNAL_TIMEOUT 50000
 
@@ -287,7 +289,6 @@ void loop()
 		{
 			cur_state = 1;
 		}
-
 		else if (current_t > target_t + T_HYSTERESIS)
 		{
 			cur_state = 0;
@@ -297,14 +298,22 @@ void loop()
 	{
 		cur_state = override_state;
 	}
-	if (relay_t > CRITICAL_T)
-	{
-		//Serial.printf("Critical overheat, t = %d\n", relay_t);
-		cur_state = 0;
-		overheat = 1;
-	}
-	else overheat = 0;
-	digitalWrite(RELAY_PIN, cur_state);
+  if (!overheat)
+  {
+    if (relay_t > CRITICAL_T)
+    {
+      overheat = 1;
+    }
+  }
+	else 
+  {
+    if (relay_t < CRITICAL_T - RELAY_COOLDOWN_T)
+    {
+      overheat = 0;
+    }
+  }
+  if (cur_state && !overheat) digitalWrite(RELAY_PIN, 1);
+  else digitalWrite(RELAY_PIN, 0);
 	if (u) 
 	{
 		Serial.printf("State %d Relay t %d Internal t %d External t %d Current t %d Target t %d\n", cur_state, relay_t, internal_t, external_t, current_t, target_t);