diff --git a/lambda-test/rules-test.c b/lambda-test/rules-test.c
index e12da95..cf428f1 100644
--- a/lambda-test/rules-test.c
+++ b/lambda-test/rules-test.c
@@ -23,60 +23,56 @@
 
 static bool testAirgate50(void) {
 
-	Measurement meas = {0, 0, 0};
+	Measurement meas = {0, 0, 0, 0};
 
-	resetRules();
+	resetRules(true);
 	dir = burning_down;
 	reason(meas);
 	assertFalse(rules[0].fired);
 
-	resetRules();
+	resetRules(true);
 	dir = none;
 	reason(meas);
 	assertFalse(rules[0].fired);
 
-	resetRules();
+	resetRules(true);
 	dir = firing_up;
 	reason(meas);
 	assertFalse(rules[0].fired);
 
-	resetRules();
+	resetRules(true);
 	dir = burning;
 	reason(meas);
 	assertFalse(rules[0].fired);
 
-	resetRules();
-	dir = warm_start;
-	reason(meas);
-	assertFalse(rules[0].fired);
+	meas.tempI = TEMP_AIRGATE_50;
+	meas.lambda = LAMBDA_TOO_LEAN;
 
-	meas.tempI = 500;
-	meas.lambda = 1500;
-
-	resetRules();
+	resetRules(true);
 	dir = burning_down;
 	reason(meas);
 	assertFalse(rules[0].fired);
 
-	resetRules();
+	resetRules(true);
 	dir = none;
 	reason(meas);
 	assertFalse(rules[0].fired);
 
-	resetRules();
+	resetRules(true);
 	dir = firing_up;
 	reason(meas);
 	assertTrue(rules[0].fired);
 	assertTrue(50 == airgate);
 
-	resetRules();
-	dir = burning;
+	// should not fire if airgate == 50
+	resetRules(false);
+	dir = firing_up;
 	reason(meas);
-	assertTrue(rules[0].fired);
+	assertFalse(rules[0].fired);
 	assertTrue(50 == airgate);
 
-	resetRules();
-	dir = warm_start;
+	resetRules(true);
+	dir = burning;
 	reason(meas);
 	assertTrue(rules[0].fired);
 	assertTrue(50 == airgate);
@@ -88,57 +84,47 @@
 
 static bool testAirgate25(void) {
 
-	Measurement meas = {999, 0, 0};
+	Measurement meas = {999, 0, 0, 0};
 
-	resetRules();
+	resetRules(true);
 	dir = firing_up;
 	reason(meas);
 	assertFalse(rules[1].fired);
 
-	resetRules();
+	resetRules(true);
 	dir = none;
 	reason(meas);
 	assertFalse(rules[1].fired);
 
-	resetRules();
+	resetRules(true);
 	dir = burning_down;
 	reason(meas);
 	assertFalse(rules[1].fired);
 
-	resetRules();
+	resetRules(true);
 	dir = burning;
 	reason(meas);
 	assertFalse(rules[1].fired);
 
-	resetRules();
-	dir = warm_start;
-	reason(meas);
-	assertFalse(rules[1].fired);
+	meas.tempI = TEMP_AIRGATE_25 - 1;
+	meas.lambda = LAMBDA_TOO_LEAN;
 
-	meas.tempI = 699;
-	meas.lambda = 1500;
-
-	resetRules();
+	resetRules(true);
 	dir = firing_up;
 	reason(meas);
 	assertFalse(rules[1].fired);
 
-	resetRules();
+	resetRules(true);
 	dir = none;
 	reason(meas);
 	assertFalse(rules[1].fired);
 
-	resetRules();
+	resetRules(true);
 	dir = burning;
 	reason(meas);
 	assertFalse(rules[1].fired);
 
-	resetRules();
-	dir = warm_start;
-	reason(meas);
-	assertFalse(rules[1].fired);
-
-	resetRules();
+	resetRules(true);
 	dir = burning_down;
 	reason(meas);
 	assertTrue(rules[1].fired);
@@ -151,57 +137,47 @@
 
 static bool testAirgateClose(void) {
 
-	Measurement meas = {999, 0, 0};
+	Measurement meas = {999, 0, 0, 0};
 
-	resetRules();
+	resetRules(true);
 	dir = firing_up;
 	reason(meas);
 	assertFalse(rules[2].fired);
 
-	resetRules();
+	resetRules(true);
 	dir = none;
 	reason(meas);
 	assertFalse(rules[2].fired);
 
-	resetRules();
+	resetRules(true);
 	dir = burning_down;
 	reason(meas);
 	assertFalse(rules[2].fired);
 
-	resetRules();
+	resetRules(true);
 	dir = burning;
 	reason(meas);
 	assertFalse(rules[2].fired);
 
-	resetRules();
-	dir = warm_start;
-	reason(meas);
-	assertFalse(rules[2].fired);
+	meas.tempI = TEMP_AIRGATE_0 - 1;
+	meas.lambda = LAMBDA_MAX;
 
-	meas.tempI = 399;
-	meas.lambda = 1500;
-
-	resetRules();
+	resetRules(true);
 	dir = firing_up;
 	reason(meas);
 	assertFalse(rules[2].fired);
 
-	resetRules();
+	resetRules(true);
 	dir = none;
 	reason(meas);
 	assertFalse(rules[2].fired);
 
-	resetRules();
+	resetRules(true);
 	dir = burning;
 	reason(meas);
 	assertFalse(rules[2].fired);
 
-	resetRules();
-	dir = warm_start;
-	reason(meas);
-	assertFalse(rules[2].fired);
-
-	resetRules();
+	resetRules(true);
 	dir = burning_down;
 	reason(meas);
 	assertTrue(rules[2].fired);
@@ -214,50 +190,45 @@
 
 static bool testTooRich(void) {
 
-	Measurement meas = {0, 0, 0};
+	Measurement meas = {0, 0, 0, 0};
 	dir = none;
 
 	setHeaterState(heaterStateReady);
 
-	meas.tempI = 100;
-	meas.lambda = 2000;
-	resetRules();
+	meas.tempI = TEMP_FIRE_OUT;
+	meas.lambda = LAMBDA_MAX;
+	resetRules(true);
 	reason(meas);
 	assertFalse(rules[3].fired);
 
-	meas.tempI = 101;
-	meas.lambda = 2000;
-	resetRules();
+	meas.tempI = TEMP_FIRE_OUT + 1;
+	meas.lambda = LAMBDA_MAX;
+	resetRules(true);
 	reason(meas);
 	assertFalse(rules[3].fired);
 
-	meas.tempI = 100;
-	meas.lambda = 1199;
-	resetRules();
+	meas.tempI = TEMP_FIRE_OUT;
+	meas.lambda = LAMBDA_TOO_RICH - 1;
+	resetRules(true);
 	reason(meas);
 	assertFalse(rules[3].fired);
 
-	meas.tempI = 101;
-	meas.lambda = 1199;
-	resetRules();
+	meas.tempI = TEMP_FIRE_OUT + 1;
+	meas.lambda = LAMBDA_TOO_RICH - 1;
+	resetRules(true);
 	airgate = 100;
 	reason(meas);
 	assertFalse(rules[3].fired);
 	assertTrue(100 == airgate);
 
-	meas.tempI = 101;
-	meas.lambda = 1199;
-	resetRules();
+	meas.tempI = TEMP_FIRE_OUT + 1;
+	meas.lambda = LAMBDA_TOO_RICH - 1;
+	resetRules(true);
 	airgate = 50;
 	reason(meas);
 	assertTrue(rules[3].fired);
 	assertTrue(100 == airgate);
 
-	meas.lambda = 1400;
-	age = 0;
-	reason(meas);
-	assertFalse(rules[3].fired);
-
 	cancelAlert(false);
 
 	return true;
@@ -265,44 +236,39 @@
 
 static bool testTooLean(void) {
 
-	Measurement meas = {0, 0, 0};
+	Measurement meas = {0, 0, 0, 0};
 	dir = none;
 
 	setHeaterState(heaterStateReady);
 
-	meas.tempI = 500;
-	meas.lambda = 1501;
-	resetRules();
+	meas.tempI = TEMP_AIRGATE_50;
+	meas.lambda = LAMBDA_TOO_LEAN + 1;
+	resetRules(true);
 	reason(meas);
 	assertFalse(rules[4].fired);
 
-	meas.tempI = 501;
+	meas.tempI = TEMP_AIRGATE_50 + 1;
 	meas.lambda = 1300;
-	resetRules();
+	resetRules(true);
 	reason(meas);
 	assertFalse(rules[4].fired);
 
-	meas.tempI = 501;
-	meas.lambda = 1501;
-	resetRules();
+	meas.tempI = TEMP_AIRGATE_50 + 1;
+	meas.lambda = LAMBDA_TOO_LEAN + 1;
+	resetRules(true);
 	airgate = 50;
 	reason(meas);
 	assertFalse(rules[4].fired);
 	assertTrue(50 == airgate);
 
-	meas.tempI = 501;
-	meas.lambda = 1501;
-	resetRules();
+	meas.tempI = TEMP_AIRGATE_50 + 1;
+	meas.lambda = LAMBDA_TOO_LEAN + 1;
+	resetRules(true);
 	airgate = 100;
 	reason(meas);
 	assertTrue(rules[4].fired);
 	assertTrue(50 == airgate);
 
-	meas.lambda = 1400;
-	age = 0;
-	reason(meas);
-	assertFalse(rules[4].fired);
-
 	cancelAlert(false);
 
 	return true;
@@ -310,8 +276,8 @@
 
 static bool testFireOut(void) {
 
-	resetRules();
-	Measurement meas = {0, 0, 0};
+	resetRules(true);
+	Measurement meas = {0, 0, 0, 0};
 	dir = firing_up;
 
 	meas.tempI = 50;
@@ -319,22 +285,22 @@
 	reason(meas);
 	assertFalse(rules[5].fired);
 
-	meas.tempI = 100;
+	meas.tempI = TEMP_FIRE_OUT;
 	age = 0;
 	reason(meas);
 	assertFalse(rules[5].fired);
 
-	meas.tempI = 125;
+	meas.tempI = TEMP_FIRE_OUT_RESET;
 	age = 0;
 	reason(meas);
 	assertFalse(rules[5].fired);
 
-	meas.tempI = 99;
+	meas.tempI = TEMP_FIRE_OUT - 1;
 	age = 0;
 	reason(meas);
 	assertTrue(rules[5].fired);
 
-	meas.tempI = 125;
+	meas.tempI = TEMP_FIRE_OUT_RESET;
 	age = 0;
 	reason(meas);
 	assertFalse(rules[5].fired);
@@ -344,15 +310,42 @@
 	return true;
 }
 
-static bool testHeaterReady(void) {
+static bool testWarmStart(void) {
 
-	resetRules();
-	resetTime();
-	Measurement meas = {0, 0, 0};
+	resetRules(true);
+	Measurement meas = {0, 0, 0, 0};
+
+	age = 0;
+	airgate = 50;
+
+	setHeaterOn(false);
+	reason(meas);
+	assertTrue(50 == airgate);
+	assertTrue(heaterStateOff == getHeaterState());
+	assertFalse(rules[6].fired);
+
+	age = 0;
 	dir = firing_up;
 
 	setHeaterOn(false);
-	meas.current = 1300;
+	reason(meas);
+	assertTrue(100 == airgate);
+	assertTrue(heaterStateUp == getHeaterState());
+	assertTrue(rules[6].fired);
+
+	cancelAlert(false);
+
+	return true;
+}
+
+static bool testHeaterReady(void) {
+
+	resetRules(true);
+	resetTime();
+	Measurement meas = {0, 0, 0, 0};
+
+	setHeaterOn(false);
+	meas.current = milliAmpsReady;
 	reason(meas);
 	assertTrue(heaterStateOff == getHeaterState());
 
@@ -362,7 +355,7 @@
 	assertTrue(heaterStateUp == getHeaterState());
 
 	setHeaterOn(true);
-	meas.current = 1300;
+	meas.current = milliAmpsReady;
 	reason(meas);
 	assertTrue(heaterStateReady == getHeaterState());
 
@@ -373,9 +366,9 @@
 
 static bool testHeaterFaultNoconn(void) {
 
-	resetRules();
+	resetRules(true);
 	resetTime();
-	Measurement meas = {0, 0, 0};
+	Measurement meas = {0, 0, 0, 0};
 	dir = firing_up;
 
 	setHeaterOn(true);
@@ -390,9 +383,9 @@
 
 static bool testHeaterFaultShort(void) {
 
-	resetRules();
+	resetRules(true);
 	resetTime();
-	Measurement meas = {0, 0, 0};
+	Measurement meas = {0, 0, 0, 0};
 	dir = firing_up;
 
 	setHeaterOn(true);
@@ -407,9 +400,9 @@
 
 static bool testHeaterFaultNoheat(void) {
 
-	resetRules();
+	resetRules(true);
 	resetTime();
-	Measurement meas = {0, 0, 0};
+	Measurement meas = {0, 0, 0, 0};
 	dir = firing_up;
 
 	setHeaterOn(true);
@@ -426,20 +419,42 @@
 	return true;
 }
 
-static bool testHeaterTimeout(void) {
+static bool testHeaterTimeout0(void) {
 
-	resetRules();
+	resetRules(true);
 	resetTime();
-	Measurement meas = {0, 0, 0};
-	dir = firing_up;
+	Measurement meas = {0, 0, 0, 0};
 
 	setHeaterOn(true);
 
-	// more than 3 hours below 400°C
+	// equal or more than 30 mins below TEMP_FIRE_OUT
+	addTime(1800);
+
+	meas.tempI = TEMP_FIRE_OUT - 1;
+	meas.lambda = LAMBDA_MAX;
+	meas.current = milliAmpsReady;
+	reason(meas);
+	assertTrue(heaterStateOff == getHeaterState());
+
+	cancelAlert(false);
+
+	return true;
+}
+
+static bool testHeaterTimeout1(void) {
+
+	resetRules(true);
+	resetTime();
+	Measurement meas = {0, 0, 0, 0};
+
+	setHeaterOn(true);
+
+	// equal or more than 3 hours below TEMP_AIRGATE_0
 	addTime(10800UL);
 
-	meas.tempI = 300;
-	meas.current = 1300;
+	meas.tempI = TEMP_AIRGATE_0 - 1;
+	meas.lambda = LAMBDA_MAX;
+	meas.current = milliAmpsReady;
 	reason(meas);
 	assertTrue(heaterStateOff == getHeaterState());
 
@@ -450,45 +465,45 @@
 
 static bool testReasonDirBurnUp(void) {
 
-	resetRules();
-	Measurement meas = {0, 0, 2000};
+	resetRules(true);
+	Measurement meas = {0, 0, 2000, 0};
 
 	age = 0;
 	reason(meas);
 	assertTrue(dir == none);
 
 	meas.tempI = 9;
-	meas.lambda = 2000;
+	meas.lambda = LAMBDA_MAX;
 	age = 180;
 	reason(meas);
 	assertTrue(dir == none);
 
-	meas.tempI = 100;
-	meas.lambda = 2000;
+	meas.tempI = TEMP_FIRE_OUT;
+	meas.lambda = LAMBDA_MAX;
 	age = 180;
 	reason(meas);
 	assertTrue(dir == firing_up);
 
-	meas.tempI = 699;
-	meas.lambda = 2000;
+	meas.tempI = TEMP_AIRGATE_25 - 1;
+	meas.lambda = LAMBDA_MAX;
 	age = 180;
 	reason(meas);
 	assertTrue(dir == firing_up);
 
-	meas.tempI = 699;
-	meas.lambda = 2000;
+	meas.tempI = TEMP_AIRGATE_25 - 1;
+	meas.lambda = LAMBDA_MAX;
 	age = 180;
 	reason(meas);
 	assertTrue(dir == none);
 
-	meas.tempI = 700;
-	meas.lambda = 1899;
+	meas.tempI = TEMP_AIRGATE_25;
+	meas.lambda = LAMBDA_BURNING - 1;
 	age = 180;
 	reason(meas);
 	assertTrue(dir == burning);
 
-	meas.tempI = 701;
-	meas.lambda = 1900;
+	meas.tempI = TEMP_AIRGATE_25 + 1;
+	meas.lambda = LAMBDA_BURNING;
 	age = 180;
 	reason(meas);
 	assertTrue(dir == burning);
@@ -500,39 +515,39 @@
 
 static bool testReasonDirBurnDown(void) {
 
-	resetRules();
-	Measurement meas = {999, 0, 1999};
+	resetRules(true);
+	Measurement meas = {999, 0, 1999, 0};
 
 	age = 0;
 	reason(meas);
 	assertTrue(dir == none);
 
 	meas.tempI = 800;
-	meas.lambda = 1899;
+	meas.lambda = LAMBDA_BURNING - 1;
 	age = 180;
 	reason(meas);
 	assertTrue(dir == burning);
 
-	meas.tempI = 700;
-	meas.lambda = 2000;
+	meas.tempI = TEMP_AIRGATE_25;
+	meas.lambda = LAMBDA_MAX;
 	age = 180;
 	reason(meas);
 	assertTrue(dir == burning);
 
-	meas.tempI = 699;
-	meas.lambda = 1899;
+	meas.tempI = TEMP_AIRGATE_25 - 1;
+	meas.lambda = LAMBDA_BURNING - 1;
 	age = 180;
 	reason(meas);
 	assertTrue(dir == burning);
 
-	meas.tempI = 699;
-	meas.lambda = 2000;
+	meas.tempI = TEMP_AIRGATE_25 - 1;
+	meas.lambda = LAMBDA_MAX;
 	age = 180;
 	reason(meas);
 	assertTrue(dir == none);
 
-	meas.tempI = 100;
-	meas.lambda = 2000;
+	meas.tempI = TEMP_FIRE_OUT;
+	meas.lambda = LAMBDA_MAX;
 	age = 180;
 	reason(meas);
 	assertTrue(dir == burning_down);
@@ -542,40 +557,6 @@
 	return true;
 }
 
-static bool testReasonDirWarmStart(void) {
-
-	resetRules();
-	Measurement meas = {999, 0, 1999};
-
-	age = 0;
-	reason(meas);
-	assertTrue(dir == none);
-
-	meas.tempI = 699;
-	meas.lambda = 2000;
-	age = 180;
-	reason(meas);
-	assertTrue(dir == burning_down);
-
-	meas.tempI = 100;
-	meas.lambda = 2000;
-	age = 180;
-	reason(meas);
-	assertTrue(dir == burning_down);
-
-	meas.tempI = 120;
-	meas.lambda = 2000;
-	age = 180;
-	reason(meas);
-	assertTrue(dir == warm_start);
-	assertTrue(heaterStateUp == getHeaterState());
-	assertTrue(airgate == 100);
-
-	cancelAlert(false);
-
-	return true;
-}
-
 /* Test "class" */
 static const char class[] PROGMEM = "rules";
 
@@ -586,14 +567,15 @@
 static const char testTooRich_P[] PROGMEM = "testTooRich";
 static const char testTooLean_P[] PROGMEM = "testTooLean";
 static const char testFireOut_P[] PROGMEM = "testFireOut";
+static const char testWarmStart_P[] PROGMEM = "testWarmStart";
 static const char testHeaterReady_P[] PROGMEM = "testHeaterReady";
 static const char testHeaterFaultNoconn_P[] PROGMEM = "testHeaterFaultNoconn";
 static const char testHeaterFaultShort_P[] PROGMEM = "testHeaterFaultShort";
 static const char testHeaterFaultNoheat_P[] PROGMEM = "testHeaterFaultNoheat";
-static const char testHeaterTimeout_P[] PROGMEM = "testHeaterTimeout";
+static const char testHeaterTimeout0_P[] PROGMEM = "testHeaterTimeout0";
+static const char testHeaterTimeout1_P[] PROGMEM = "testHeaterTimeout1";
 static const char testReasonDirBurnUp_P[] PROGMEM = "testReasonDirBurnUp";
 static const char testReasonDirBurnDown_P[] PROGMEM = "testReasonDirBurnDown";
-static const char testReasonDirWarmStart_P[] PROGMEM = "testReasonDirWarmStart";
 
 /* Tests */
 static TestCase const tests[] = {
@@ -603,14 +585,15 @@
 		{class, testTooRich_P, testTooRich},
 		{class, testTooLean_P, testTooLean},
 		{class, testFireOut_P, testFireOut},
+		{class, testWarmStart_P, testWarmStart},
 		{class, testHeaterReady_P, testHeaterReady},
 		{class, testHeaterFaultNoconn_P, testHeaterFaultNoconn},
 		{class, testHeaterFaultShort_P, testHeaterFaultShort},
 		{class, testHeaterFaultNoheat_P, testHeaterFaultNoheat},
-		{class, testHeaterTimeout_P, testHeaterTimeout},
+		{class, testHeaterTimeout0_P, testHeaterTimeout0},
+		{class, testHeaterTimeout1_P, testHeaterTimeout1},
 		{class, testReasonDirBurnUp_P, testReasonDirBurnUp},
-		{class, testReasonDirBurnDown_P, testReasonDirBurnDown},
-		{class, testReasonDirWarmStart_P, testReasonDirWarmStart}
+		{class, testReasonDirBurnDown_P, testReasonDirBurnDown}
 };
 
 TestClass rulesClass = {tests, sizeof(tests) / sizeof(tests[0])};
diff --git a/lambda/command.c b/lambda/command.c
index 4df94b6..5392ec2 100644
--- a/lambda/command.c
+++ b/lambda/command.c
@@ -42,7 +42,7 @@
 		simulation = true;
 		resetTime();
 		resetDisplay();
-		resetRules();
+		resetRules(true);
 		setHeaterOn(true);
 		beep(1, 1, 31);
 	}
@@ -50,7 +50,7 @@
 		// simulation disable
 		resetTime();
 		resetDisplay();
-		resetRules();
+		resetRules(true);
 		simulation = false;
 		beep(1, 1, 31);
 	}
diff --git a/lambda/display.c b/lambda/display.c
index f23e049..6d1ad5f 100644
--- a/lambda/display.c
+++ b/lambda/display.c
@@ -136,7 +136,6 @@
 				case firing_up: hint = " >"; break;
 				case burning: hint = " ^"; break;
 				case burning_down: hint = " <"; break;
-				case warm_start: hint = " +"; break;
 				default: hint = " -"; break;
 			}
 			displayMeas(measLatest, hint);
diff --git a/lambda/rules.c b/lambda/rules.c
index 23bd95a..18291f0 100644
--- a/lambda/rules.c
+++ b/lambda/rules.c
@@ -13,6 +13,8 @@
 #include "rules.h"
 #include "messages.h"
 
+#include "usart.h"
+
 uint8_t age = 0;
 FireDir dir = none;
 uint8_t airgate = 100;
@@ -27,9 +29,9 @@
  */
 static void airgate50(bool* const fired, int8_t const dir,
 		Measurement const meas) {
-	if (! *fired && (dir == firing_up || dir == burning || dir == warm_start) &&
+	if ((dir == firing_up || dir == burning) &&
 			meas.tempI >= TEMP_AIRGATE_50 && meas.lambda >= LAMBDA_TOO_LEAN &&
-			airgate > 50) {
+			airgate != 50) {
 		airgate = 50;
 		alert_P(BEEPS, LENGTH, TONE, PSTR(MSG_AIRGATE_50_0), PSTR(""), false);
 		*fired = true;
@@ -42,7 +44,7 @@
  */
 static void airgate25(bool* const fired, int8_t const dir,
 		Measurement const meas) {
-	if (! *fired && dir == burning_down && meas.tempI < TEMP_AIRGATE_25 &&
+	if (dir == burning_down && meas.tempI < TEMP_AIRGATE_25 &&
 			meas.lambda >= LAMBDA_TOO_LEAN && airgate > 25) {
 		airgate = 25;
 		alert_P(BEEPS, LENGTH, TONE, PSTR(MSG_AIRGATE_25_0), PSTR(""), false);
@@ -56,8 +58,8 @@
  */
 static void airgateClose(bool* const fired, int8_t const dir,
 		Measurement const meas) {
-	if (! *fired && dir == burning_down && meas.tempI < TEMP_AIRGATE_0 &&
-			meas.lambda >= LAMBDA_TOO_LEAN && airgate > 0) {
+	if (dir == burning_down && meas.tempI < TEMP_AIRGATE_0 &&
+			meas.lambda >= LAMBDA_MAX && airgate > 0) {
 		setHeaterOn(false);
 		airgate = 0;
 		alert_P(BEEPS, LENGTH, TONE,
@@ -71,7 +73,7 @@
  */
 static void tooRich(bool* const fired, int8_t const dir,
 		Measurement const meas) {
-	if (! *fired && meas.tempI > TEMP_FIRE_OUT &&
+	if (meas.tempI > TEMP_FIRE_OUT &&
 			meas.lambda < LAMBDA_TOO_RICH &&
 			getHeaterState() == heaterStateReady && airgate < 100) {
 		airgate = 100;
@@ -79,9 +81,6 @@
 				PSTR(MSG_TOO_RICH_0), PSTR(MSG_TOO_RICH_1), false);
 		*fired = true;
 	}
-	if (meas.lambda >= LAMBDA_TOO_RICH_RESET) {
-		*fired = false;
-	}
 }
 
 /**
@@ -89,16 +88,13 @@
  */
 static void tooLean(bool* const fired, int8_t const dir,
 		Measurement const meas) {
-	if (! *fired && meas.tempI > TEMP_AIRGATE_50 &&
+	if (meas.tempI > TEMP_AIRGATE_50 &&
 			meas.lambda > LAMBDA_TOO_LEAN &&
 			getHeaterState() == heaterStateReady && airgate > 50) {
 		airgate = 50;
 		alert_P(BEEPS, LENGTH, TONE, PSTR(MSG_AIRGATE_50_0), PSTR(""), false);
 		*fired = true;
 	}
-	if (meas.lambda <= LAMBDA_TOO_LEAN_RESET) {
-		*fired = false;
-	}
 }
 
 /**
@@ -117,6 +113,26 @@
 }
 
 /**
+ * Resets rules and some state and switches on the heating if it seems that
+ * wood was added or the oven was fired up without resetting.
+ */
+static void warmStart(bool* const fired, int8_t const dir,
+		Measurement const meas) {
+	if (dir == firing_up && ! isHeaterOn() &&
+			getHeaterState() != heaterStateFault) {
+		// it seems wood has been added or - probably more likely - oven
+		// was fired up without resetting. Should probably work that way
+		// anyway, making manual reset unnecessary?
+		// TODO make a complete reset including time?
+		resetRules(false);
+		airgate = 100;
+		rulesMeasMax.tempI = meas.tempI;
+		setHeaterOn(true);
+		*fired = true;
+	}
+}
+
+/**
  * Notifies that the heater is ready and sets the corresponding state.
  */
 static void heaterReady(bool* const fired, int8_t const dir,
@@ -160,30 +176,25 @@
 		return;
 	}
 	uint32_t heaterUptime = getHeaterUptime();
-	if (heaterUptime >= 1800 && meas.tempI < TEMP_FIRE_OUT) {
+	if (heaterUptime >= 1800 && meas.tempI < TEMP_FIRE_OUT &&
+			meas.lambda >= LAMBDA_MAX) {
 		setHeaterOn(false);
 		alert_P(BEEPS, LENGTH, TONE, PSTR(MSG_FIRE_OUT_0), PSTR(""), false);
 	}
-	if (heaterUptime >= 10800 && meas.tempI < TEMP_AIRGATE_0) {
+	if (heaterUptime >= 10800 && meas.tempI < TEMP_AIRGATE_0 &&
+			meas.lambda >= LAMBDA_MAX) {
 		setHeaterOn(false);
-		alert_P(3, 5, TONE, PSTR(MSG_HEATER_OFF_0),
-						PSTR(MSG_HEATER_OFF_1), false);
+		if (airgate > 0) {
+			alert_P(BEEPS, LENGTH, TONE, PSTR(MSG_AIRGATE_CLOSE_0), PSTR(""),
+					false);
+		} else {
+			alert_P(3, 5, TONE, PSTR(MSG_HEATER_OFF_0), PSTR(MSG_HEATER_OFF_1),
+					false);
+		}
 	}
 }
 
 /**
- * Rules applied to every nth averaged measurement.
- */
-Rule rules[] = {
-		{false, airgate50},
-		{false, airgate25},
-		{false, airgateClose},
-		{false, tooRich},
-		{false, tooLean},
-		{false, fireOut}
-};
-
-/**
  * Heater rules applied to each not averaged measured heater current value.
  */
 Rule heaterRules[] = {
@@ -192,6 +203,19 @@
 		{false, heaterTimeout}
 };
 
+/**
+ * Rules applied to every nth averaged measurement.
+ */
+Rule rules[] = {
+		{false, airgate50},
+		{false, airgate25},
+		{false, airgateClose},
+		{false, tooRich},
+		{false, tooLean},
+		{false, fireOut},
+		{false, warmStart}
+};
+
 int8_t getDir(void) {
 	return dir;
 }
@@ -199,6 +223,12 @@
 // called about every second
 void reason(Measurement const meas) {
 
+	// rules applied to each measurement
+	size_t heaterRulesSize = sizeof(heaterRules) / sizeof(heaterRules[0]);
+	for (size_t i = 0; i < heaterRulesSize; i++) {
+		heaterRules[i].cond(&(heaterRules[i].fired), dir, meas);
+	}
+
 	// rules applied to every 10th measurement
 	if (age % 10 == 0) {
 		size_t rulesSize = sizeof(rules) / sizeof(rules[0]);
@@ -207,12 +237,6 @@
 		}
 	}
 
-	// rules applied to each measurement
-	size_t heaterRulesSize = sizeof(heaterRules) / sizeof(heaterRules[0]);
-	for (size_t i = 0; i < heaterRulesSize; i++) {
-		heaterRules[i].cond(&(heaterRules[i].fired), dir, meas);
-	}
-
 	age++;
 
 	// init previous measurements with current measurements
@@ -226,34 +250,17 @@
 	if (age >= AGE_MEAS_PREV) {
 		dir = none;
 		if ((meas.tempI - rulesMeasPrev.tempI) >= TEMP_DELTA_UP &&
-				rulesMeasMax.tempI < TEMP_MIN && meas.lambda >= LAMBDA_MAX) {
+				meas.tempI < TEMP_MIN && meas.lambda >= LAMBDA_BURNING) {
 			dir = firing_up;
 		}
-		if (meas.tempI >= TEMP_MIN || meas.lambda < LAMBDA_MAX) {
+		if (meas.tempI >= TEMP_MIN || meas.lambda < LAMBDA_BURNING) {
 			dir = burning;
 		}
 		if ((rulesMeasPrev.tempI - meas.tempI) >= TEMP_DELTA_DOWN &&
-				meas.tempI < TEMP_MIN && rulesMeasMax.tempI >= TEMP_MIN &&
-				meas.lambda >= LAMBDA_MAX) {
+				meas.tempI < TEMP_MIN && meas.lambda >= LAMBDA_BURNING &&
+				rulesMeasMax.tempI >= TEMP_AIRGATE_50) {
 			dir = burning_down;
 		}
-		if ((meas.tempI - rulesMeasPrev.tempI) >= TEMP_DELTA_UP &&
-				meas.tempI < TEMP_MIN && rulesMeasMax.tempI >= TEMP_MIN) {
-			// it seems wood has been added or - probably more likely - oven
-			// was fired up without resetting. Should probably work that way
-			// anyway, making manual reset unnecessary?
-			// TODO make a complete reset including time?
-			dir = warm_start;
-			rulesMeasMax.tempI = meas.tempI;
-			size_t rulesSize = sizeof(rules) / sizeof(rules[0]);
-			for (size_t i = 0; i < rulesSize; i++) {
-				rules[i].fired = false;
-			}
-			if (! isHeaterOn() && getHeaterState() != heaterStateFault) {
-				setHeaterOn(true);
-			}
-			airgate = 100;
-		}
 
 		rulesMeasPrev = meas;
 		age = 0;
@@ -262,13 +269,15 @@
 	rulesMeasMax.tempI = MAX(rulesMeasMax.tempI, meas.tempI);
 }
 
-void resetRules(void) {
-	prevInit = false;
-	rulesMeasMax.tempI = 0;
+void resetRules(bool const state) {
+	if (state) {
+		prevInit = false;
+		rulesMeasMax.tempI = 0;
 
-	age = 0;
-	dir = none;
-	airgate = 100;
+		age = 0;
+		dir = none;
+		airgate = 100;
+	}
 
 	size_t rulesSize = sizeof(rules) / sizeof(rules[0]);
 	for (size_t i = 0; i < rulesSize; i++) {
diff --git a/lambda/rules.h b/lambda/rules.h
index 50026fa..c0b78c4 100644
--- a/lambda/rules.h
+++ b/lambda/rules.h
@@ -36,22 +36,22 @@
 #define TEMP_FIRE_OUT 100
 /** Min. temperature at which to consider the fire to fire up again */
 #define TEMP_FIRE_OUT_RESET 125
+/** Max. lambda value that can be measured */
+#define LAMBDA_MAX 2000
 /** Fire is considered fully burning if lambda is below this value */
-#define LAMBDA_MAX 1900
+#define LAMBDA_BURNING 1900
 /** Combustion is considered too rich if lambda is below this value */
 #define LAMBDA_TOO_RICH 1200
-/** Combustion is considered lean enough again if lambda is above this value */
-#define LAMBDA_TOO_RICH_RESET 1400
-/** Combustion is considered too lean if lambda is above this value */
-#define LAMBDA_TOO_LEAN 1500
-/** Combustion is considered rich enough again if lambda is below this value */
-#define LAMBDA_TOO_LEAN_RESET 1400
+/**
+ * Combustion is considered too lean if lambda is above this value
+ * Too lean here rather means lean enough so the air gate can be set to 50%
+ */
+#define LAMBDA_TOO_LEAN 1400
 
 typedef enum {
 	none = 0,
 	firing_up = 1,
 	burning = 2,
-	warm_start = 3,
 	burning_down = -1
 } FireDir;
 
@@ -77,6 +77,6 @@
 /**
  * Resets all rules and internal state.
  */
-void resetRules(void);
+void resetRules(bool state);
 
 #endif /* RULES_H_ */