diff --git a/platformio.ini b/platformio.ini
index 372919b99..ecb72a3fe 100755
--- a/platformio.ini
+++ b/platformio.ini
@@ -67,7 +67,7 @@ build_flags               = ${esp82xx_defaults.build_flags}
 
 [core_2_5_2]
 ; *** Esp8266 core for Arduino version 2.5.2
-platform                  = espressif8266@~2.2.1
+platform                  = espressif8266@~2.2.2
 build_flags               = ${esp82xx_defaults.build_flags}
                             -Wl,-Teagle.flash.1m.ld
 ; Code optimization see https://github.com/esp8266/Arduino/issues/5790#issuecomment-475672473
diff --git a/sonoff/_changelog.ino b/sonoff/_changelog.ino
index 0ebffba3b..a1871ad18 100644
--- a/sonoff/_changelog.ino
+++ b/sonoff/_changelog.ino
@@ -7,6 +7,7 @@
  * Add define USE_DHT to my_user_config.h to save space in sonoff-basic.bin
  * Change TLS+AWS IoT optimization for speed, code and memory footprint
  * Add command SetOption40 0..250 to disable button functionality if activated for over 0.1 second. Needs SetOption1 1 and SetOption13 0 (#5449)
+ * Change converted double to float in rules, and replaced trigonometric functions from stdlib with smaller versions.
  *
  * 6.5.0.15 20190606
  * Change pubsubclient MQTT_KEEPALIVE from 10 to 30 seconds in preparation of AWS IoT support
diff --git a/sonoff/sonoff.ino b/sonoff/sonoff.ino
index 8f14f714b..02ea25524 100755
--- a/sonoff/sonoff.ino
+++ b/sonoff/sonoff.ino
@@ -1939,8 +1939,8 @@ void MqttShowState(void)
   ResponseAppend_P(PSTR(",\"" D_JSON_VCC "\":%s"), stemp1);
 #endif
 
-  ResponseAppend_P(PSTR(",\"SleepMode\":\"%s\",\"Sleep\":%u,\"LoadAvg\":%u"),
-    GetTextIndexed(stemp1, sizeof(stemp1), Settings.flag3.sleep_normal, kSleepMode), sleep, loop_load_avg);
+  ResponseAppend_P(PSTR(",\"" D_JSON_HEAPSIZE "\":%d,\"SleepMode\":\"%s\",\"Sleep\":%u,\"LoadAvg\":%u"),
+    ESP.getFreeHeap()/1024, GetTextIndexed(stemp1, sizeof(stemp1), Settings.flag3.sleep_normal, kSleepMode), sleep, loop_load_avg);
 
   for (uint32_t i = 0; i < devices_present; i++) {
 #ifdef USE_LIGHT
diff --git a/sonoff/support.ino b/sonoff/support.ino
index be441f167..41e5ffd3b 100644
--- a/sonoff/support.ino
+++ b/sonoff/support.ino
@@ -224,7 +224,7 @@ char* subStr(char* dest, char* str, const char *delim, int index)
   return sub;
 }
 
-double CharToDouble(const char *str)
+float CharToFloat(const char *str)
 {
   // simple ascii to double, because atof or strtod are too large
   char strbuf[24];
@@ -237,23 +237,23 @@ double CharToDouble(const char *str)
   if (*pt == '-') { sign = -1; }
   if (*pt == '-' || *pt=='+') { pt++; }            // Skip any sign
 
-  double left = 0;
+  float left = 0;
   if (*pt != '.') {
     left = atoi(pt);                               // Get left part
     while (isdigit(*pt)) { pt++; }                 // Skip number
   }
 
-  double right = 0;
+  float right = 0;
   if (*pt == '.') {
     pt++;
     right = atoi(pt);                              // Decimal part
     while (isdigit(*pt)) {
       pt++;
-      right /= 10.0;
+      right /= 10.0f;
     }
   }
 
-  double result = left + right;
+  float result = left + right;
   if (sign < 0) {
     return -result;                                // Add negative sign
   }
@@ -650,66 +650,6 @@ void ResetGlobalValues(void)
   }
 }
 
-double FastPrecisePow(double a, double b)
-{
-  // https://martin.ankerl.com/2012/01/25/optimized-approximative-pow-in-c-and-cpp/
-  // calculate approximation with fraction of the exponent
-  int e = abs((int)b);
-  union {
-    double d;
-    int x[2];
-  } u = { a };
-  u.x[1] = (int)((b - e) * (u.x[1] - 1072632447) + 1072632447);
-  u.x[0] = 0;
-  // exponentiation by squaring with the exponent's integer part
-  // double r = u.d makes everything much slower, not sure why
-  double r = 1.0;
-  while (e) {
-    if (e & 1) {
-      r *= a;
-    }
-    a *= a;
-    e >>= 1;
-  }
-  return r * u.d;
-}
-
-float FastPrecisePowf(const float x, const float y)
-{
-//  return (float)(pow((double)x, (double)y));
-  return (float)FastPrecisePow(x, y);
-}
-
-double TaylorLog(double x)
-{
-  // https://stackoverflow.com/questions/46879166/finding-the-natural-logarithm-of-a-number-using-taylor-series-in-c
-
-  if (x <= 0.0) { return NAN; }
-  double z = (x + 1) / (x - 1);                              // We start from power -1, to make sure we get the right power in each iteration;
-  double step = ((x - 1) * (x - 1)) / ((x + 1) * (x + 1));   // Store step to not have to calculate it each time
-  double totalValue = 0;
-  double powe = 1;
-  double y;
-  for (uint32_t count = 0; count < 10; count++) {                 // Experimental number of 10 iterations
-    z *= step;
-    y = (1 / powe) * z;
-    totalValue = totalValue + y;
-    powe = powe + 2;
-  }
-  totalValue *= 2;
-/*
-  char logxs[33];
-  dtostrfd(x, 8, logxs);
-  double log1 = log(x);
-  char log1s[33];
-  dtostrfd(log1, 8, log1s);
-  char log2s[33];
-  dtostrfd(totalValue, 8, log2s);
-  AddLog_P2(LOG_LEVEL_DEBUG, PSTR("input %s, log %s, taylor %s"), logxs, log1s, log2s);
-*/
-  return totalValue;
-}
-
 uint32_t SqrtInt(uint32_t num)
 {
   if (num <= 1) {
diff --git a/sonoff/support_float.ino b/sonoff/support_float.ino
new file mode 100644
index 000000000..fc2dccf04
--- /dev/null
+++ b/sonoff/support_float.ino
@@ -0,0 +1,318 @@
+/*
+  support_float.ino - support for Sonoff-Tasmota
+
+  Copyright (C) 2019  Theo Arends
+
+  This program is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+double FastPrecisePow(double a, double b)
+{
+  // https://martin.ankerl.com/2012/01/25/optimized-approximative-pow-in-c-and-cpp/
+  // calculate approximation with fraction of the exponent
+  int e = abs((int)b);
+  union {
+    double d;
+    int x[2];
+  } u = { a };
+  u.x[1] = (int)((b - e) * (u.x[1] - 1072632447) + 1072632447);
+  u.x[0] = 0;
+  // exponentiation by squaring with the exponent's integer part
+  // double r = u.d makes everything much slower, not sure why
+  double r = 1.0;
+  while (e) {
+    if (e & 1) {
+      r *= a;
+    }
+    a *= a;
+    e >>= 1;
+  }
+  return r * u.d;
+}
+
+float FastPrecisePowf(const float x, const float y)
+{
+//  return (float)(pow((double)x, (double)y));
+  return (float)FastPrecisePow(x, y);
+}
+
+double TaylorLog(double x)
+{
+  // https://stackoverflow.com/questions/46879166/finding-the-natural-logarithm-of-a-number-using-taylor-series-in-c
+
+  if (x <= 0.0) { return NAN; }
+  double z = (x + 1) / (x - 1);                              // We start from power -1, to make sure we get the right power in each iteration;
+  double step = ((x - 1) * (x - 1)) / ((x + 1) * (x + 1));   // Store step to not have to calculate it each time
+  double totalValue = 0;
+  double powe = 1;
+  double y;
+  for (uint32_t count = 0; count < 10; count++) {                 // Experimental number of 10 iterations
+    z *= step;
+    y = (1 / powe) * z;
+    totalValue = totalValue + y;
+    powe = powe + 2;
+  }
+  totalValue *= 2;
+/*
+  char logxs[33];
+  dtostrfd(x, 8, logxs);
+  double log1 = log(x);
+  char log1s[33];
+  dtostrfd(log1, 8, log1s);
+  char log2s[33];
+  dtostrfd(totalValue, 8, log2s);
+  AddLog_P2(LOG_LEVEL_DEBUG, PSTR("input %s, log %s, taylor %s"), logxs, log1s, log2s);
+*/
+  return totalValue;
+}
+
+// All code adapted from: http://www.ganssle.com/approx.htm
+
+/// ========================================
+//  The following code implements approximations to various trig functions.
+//
+//  This is demo code to guide developers in implementing their own approximation
+// software. This code is merely meant to illustrate algorithms.
+
+inline float sinf(float x) { return sin_52(x); }
+inline float cosf(float x) { return cos_52(x); }
+inline float tanf(float x) { return tan_56(x); }
+inline float atanf(float x) { return atan_66(x); }
+inline float asinf(float x) { return asinf1(x); }
+inline float acosf(float x) { return acosf1(x); }
+inline float sqrtf(float x) { return sqrt1(x); }
+inline float powf(float x, float y) { return FastPrecisePow(x, y); }
+
+// Math constants we'll use
+double const f_pi=3.1415926535897932384626433;	// f_pi
+double const f_twopi=2.0*f_pi;			// f_pi times 2
+double const f_two_over_pi= 2.0/f_pi;		// 2/f_pi
+double const f_halfpi=f_pi/2.0;			// f_pi divided by 2
+double const f_threehalfpi=3.0*f_pi/2.0;  		// f_pi times 3/2, used in tan routines
+double const f_four_over_pi=4.0/f_pi;		// 4/f_pi, used in tan routines
+double const f_qtrpi=f_pi/4.0;			// f_pi/4.0, used in tan routines
+double const f_sixthpi=f_pi/6.0;			// f_pi/6.0, used in atan routines
+double const f_tansixthpi=tan(f_sixthpi);		// tan(f_pi/6), used in atan routines
+double const f_twelfthpi=f_pi/12.0;			// f_pi/12.0, used in atan routines
+double const f_tantwelfthpi=tan(f_twelfthpi);	// tan(f_pi/12), used in atan routines
+
+// *********************************************************
+// ***
+// ***   Routines to compute sine and cosine to 5.2 digits
+// ***  of accuracy.
+// ***
+// *********************************************************
+//
+//		cos_52s computes cosine (x)
+//
+//  Accurate to about 5.2 decimal digits over the range [0, f_pi/2].
+//  The input argument is in radians.
+//
+//  Algorithm:
+//		cos(x)= c1 + c2*x**2 + c3*x**4 + c4*x**6
+//   which is the same as:
+//		cos(x)= c1 + x**2(c2 + c3*x**2 + c4*x**4)
+//		cos(x)= c1 + x**2(c2 + x**2(c3 + c4*x**2))
+//
+float cos_52s(float x)
+{
+const float c1= 0.9999932946;
+const float c2=-0.4999124376;
+const float c3= 0.0414877472;
+const float c4=-0.0012712095;
+
+float x2;							// The input argument squared
+
+x2=x * x;
+return (c1 + x2*(c2 + x2*(c3 + c4*x2)));
+}
+
+//
+//  This is the main cosine approximation "driver"
+// It reduces the input argument's range to [0, f_pi/2],
+// and then calls the approximator.
+// See the notes for an explanation of the range reduction.
+//
+float cos_52(float x){
+	int quad;						// what quadrant are we in?
+
+	x=fmodf(x, f_twopi);				// Get rid of values > 2* f_pi
+	if(x<0)x=-x;					// cos(-x) = cos(x)
+	quad=int(x * (float)f_two_over_pi);			// Get quadrant # (0 to 3) we're in
+	switch (quad){
+	case 0: return  cos_52s(x);
+	case 1: return -cos_52s((float)f_pi-x);
+	case 2: return -cos_52s(x-(float)f_pi);
+	case 3: return  cos_52s((float)f_twopi-x);
+	}
+}
+//
+//   The sine is just cosine shifted a half-f_pi, so
+// we'll adjust the argument and call the cosine approximation.
+//
+float sin_52(float x){
+	return cos_52((float)f_halfpi-x);
+}
+
+// *********************************************************
+// ***
+// ***   Routines to compute tangent to 5.6 digits
+// ***  of accuracy.
+// ***
+// *********************************************************
+//
+//		tan_56s computes tan(f_pi*x/4)
+//
+//  Accurate to about 5.6 decimal digits over the range [0, f_pi/4].
+//  The input argument is in radians. Note that the function
+//  computes tan(f_pi*x/4), NOT tan(x); it's up to the range
+//  reduction algorithm that calls this to scale things properly.
+//
+//  Algorithm:
+//		tan(x)= x(c1 + c2*x**2)/(c3 + x**2)
+//
+float tan_56s(float x)
+{
+const float c1=-3.16783027;
+const float c2= 0.134516124;
+const float c3=-4.033321984;
+
+float x2;							// The input argument squared
+
+x2=x * x;
+return (x*(c1 + c2 * x2)/(c3 + x2));
+}
+
+//
+//  This is the main tangent approximation "driver"
+// It reduces the input argument's range to [0, f_pi/4],
+// and then calls the approximator.
+// See the notes for an explanation of the range reduction.
+// Enter with positive angles only.
+//
+// WARNING: We do not test for the tangent approaching infinity,
+// which it will at x=f_pi/2 and x=3*f_pi/2. If this is a problem
+// in your application, take appropriate action.
+//
+float tan_56(float x){
+	int octant;						// what octant are we in?
+
+	x=fmodf(x, (float)f_twopi);				// Get rid of values >2 *f_pi
+	octant=int(x * (float)f_four_over_pi);			// Get octant # (0 to 7)
+	switch (octant){
+	case 0: return       tan_56s(x                     *(float)f_four_over_pi);
+	case 1: return  1.0f/tan_56s(((float)f_halfpi-x)     *(float)f_four_over_pi);
+	case 2: return -1.0f/tan_56s((x-(float)f_halfpi)     *(float)f_four_over_pi);
+	case 3: return -     tan_56s(((float)f_pi-x)         *(float)f_four_over_pi);
+	case 4: return       tan_56s((x-(float)f_pi)         *(float)f_four_over_pi);
+	case 5: return  1.0f/tan_56s(((float)f_threehalfpi-x)*(float)f_four_over_pi);
+	case 6: return -1.0f/tan_56s((x-(float)f_threehalfpi)*(float)f_four_over_pi);
+	case 7: return -     tan_56s(((float)f_twopi-x)      *(float)f_four_over_pi);
+	}
+}
+
+// *********************************************************
+// ***
+// ***   Routines to compute arctangent to 6.6 digits
+// ***  of accuracy.
+// ***
+// *********************************************************
+//
+//		atan_66s computes atan(x)
+//
+//  Accurate to about 6.6 decimal digits over the range [0, f_pi/12].
+//
+//  Algorithm:
+//		atan(x)= x(c1 + c2*x**2)/(c3 + x**2)
+//
+float atan_66s(float x)
+{
+const float c1=1.6867629106;
+const float c2=0.4378497304;
+const float c3=1.6867633134;
+
+float x2;							// The input argument squared
+
+x2=x * x;
+return (x*(c1 + x2*c2)/(c3 + x2));
+}
+
+//
+//  This is the main arctangent approximation "driver"
+// It reduces the input argument's range to [0, f_pi/12],
+// and then calls the approximator.
+//
+//
+float atan_66(float x){
+  float y;							// return from atan__s function
+  bool complement= false;				// true if arg was >1
+  bool region= false;					// true depending on region arg is in
+  bool sign= false;					// true if arg was < 0
+
+  if (x <0 ){
+  	x=-x;
+  	sign=true;						// arctan(-x)=-arctan(x)
+  }
+  if (x > 1.0){
+  	x=1.0/x;						// keep arg between 0 and 1
+  	complement=true;
+  }
+  if (x > (float)f_tantwelfthpi){
+  	x = (x-(float)f_tansixthpi)/(1+(float)f_tansixthpi*x);	// reduce arg to under tan(f_pi/12)
+  	region=true;
+  }
+
+  y=atan_66s(x);						// run the approximation
+  if (region) y+=(float)f_sixthpi;				// correct for region we're in
+  if (complement)y=(float)f_halfpi-y;			// correct for 1/x if we did that
+  if (sign)y=-y;						// correct for negative arg
+  return (y);
+}
+
+float asinf1(float x) {
+	float d = 1.0f - x*x;
+	if (d < 0.0f) { return nanf(""); }
+	return 2 * atan_66(x / (1 + sqrt1(d)));
+}
+
+float acosf1(float x) {
+	float d = 1.0f - x*x;
+	if (d < 0.0f) { return nanf(""); }
+	float y = asinf1(sqrt1(d));
+	if (x >= 0.0f) {
+		return y;
+	} else {
+		return (float)f_pi - y;
+	}
+}
+
+// https://www.codeproject.com/Articles/69941/Best-Square-Root-Method-Algorithm-Function-Precisi
+float sqrt1(const float x)
+{
+  union
+  {
+    int i;
+    float x;
+  } u;
+  u.x = x;
+  u.i = (1<<29) + (u.i >> 1) - (1<<22);
+
+  // Two Babylonian Steps (simplified from:)
+  // u.x = 0.5f * (u.x + x/u.x);
+  // u.x = 0.5f * (u.x + x/u.x);
+  u.x =       u.x + x/u.x;
+  u.x = 0.25f*u.x + x/u.x;
+
+  return u.x;
+}
diff --git a/sonoff/xdrv_09_timers.ino b/sonoff/xdrv_09_timers.ino
index 5b7dce6fb..4de82c817 100644
--- a/sonoff/xdrv_09_timers.ino
+++ b/sonoff/xdrv_09_timers.ino
@@ -487,7 +487,7 @@ bool TimerCommand(void)
 #ifdef USE_SUNRISE
   else if (CMND_LONGITUDE == command_code) {
     if (XdrvMailbox.data_len) {
-      Settings.longitude = (int)(CharToDouble(XdrvMailbox.data) *1000000);
+      Settings.longitude = (int)(CharToFloat(XdrvMailbox.data) *1000000);
     }
     char lbuff[33];
     dtostrfd(((float)Settings.longitude) /1000000, 6, lbuff);
@@ -495,7 +495,7 @@ bool TimerCommand(void)
   }
   else if (CMND_LATITUDE == command_code) {
     if (XdrvMailbox.data_len) {
-      Settings.latitude = (int)(CharToDouble(XdrvMailbox.data) *1000000);
+      Settings.latitude = (int)(CharToFloat(XdrvMailbox.data) *1000000);
     }
     char lbuff[33];
     dtostrfd(((float)Settings.latitude) /1000000, 6, lbuff);
diff --git a/sonoff/xdrv_10_rules.ino b/sonoff/xdrv_10_rules.ino
index 61bb27796..e4da6939b 100644
--- a/sonoff/xdrv_10_rules.ino
+++ b/sonoff/xdrv_10_rules.ino
@@ -179,7 +179,7 @@ bool RulesRuleMatch(uint8_t rule_set, String &event, String &rule)
   }
 
   char rule_svalue[CMDSZ] = { 0 };
-  double rule_value = 0;
+  float rule_value = 0;
   if (compare != COMPARE_OPERATOR_NONE) {
     String rule_param = rule_name.substring(pos + strlen(compare_operator));
     for (uint32_t i = 0; i < MAX_RULE_VARS; i++) {
@@ -225,7 +225,7 @@ bool RulesRuleMatch(uint8_t rule_set, String &event, String &rule)
     if (temp_value > -1) {
       rule_value = temp_value;
     } else {
-      rule_value = CharToDouble((char*)rule_svalue);   // 0.1      - This saves 9k code over toFLoat()!
+      rule_value = CharToFloat((char*)rule_svalue);   // 0.1      - This saves 9k code over toFLoat()!
     }
     rule_name = rule_name.substring(0, pos);           // "CURRENT"
   }
@@ -235,7 +235,7 @@ bool RulesRuleMatch(uint8_t rule_set, String &event, String &rule)
   JsonObject &root = jsonBuf.parseObject(event);
   if (!root.success()) { return false; }               // No valid JSON data
 
-  double value = 0;
+  float value = 0;
   const char* str_value = root[rule_task][rule_name];
 
 //AddLog_P2(LOG_LEVEL_DEBUG, PSTR("RUL: Task %s, Name %s, Value |%s|, TrigCnt %d, TrigSt %d, Source %s, Json %s"),
@@ -248,7 +248,7 @@ bool RulesRuleMatch(uint8_t rule_set, String &event, String &rule)
 
   // Step 3: Compare rule (value)
   if (str_value) {
-    value = CharToDouble((char*)str_value);
+    value = CharToFloat((char*)str_value);
     int int_value = int(value);
     int int_rule_value = int(rule_value);
     switch (compare) {
@@ -797,15 +797,15 @@ String RulesUnsubscribe(const char * data, int data_len)
  * Parse a number value
  * Input:
  *      pNumber     - A char pointer point to a digit started string (guaranteed)
- *      value       - Reference a double variable used to accept the result
+ *      value       - Reference a float variable used to accept the result
  * Output:
  *      pNumber     - Pointer forward to next character after the number
- *      value       - double type, the result value
+ *      value       - float type, the result value
  * Return:
  *      true    - succeed
  *      false   - failed
  */
-bool findNextNumber(char * &pNumber, double &value)
+bool findNextNumber(char * &pNumber, float &value)
 {
   bool bSucceed = false;
   String sNumber = "";
@@ -818,7 +818,7 @@ bool findNextNumber(char * &pNumber, double &value)
     }
   }
   if (sNumber.length() > 0) {
-    value = CharToDouble(sNumber.c_str());
+    value = CharToFloat(sNumber.c_str());
     bSucceed = true;
   }
   return bSucceed;
@@ -826,18 +826,18 @@ bool findNextNumber(char * &pNumber, double &value)
 
 /********************************************************************************************/
 /*
- * Parse a variable (like VAR1, MEM3) and get its value (double type)
+ * Parse a variable (like VAR1, MEM3) and get its value (float type)
  * Input:
  *      pVarname    - A char pointer point to a variable name string
- *      value       - Reference a double variable used to accept the result
+ *      value       - Reference a float variable used to accept the result
  * Output:
  *      pVarname    - Pointer forward to next character after the variable
- *      value       - double type, the result value
+ *      value       - float type, the result value
  * Return:
  *      true    - succeed
  *      false   - failed
  */
-bool findNextVariableValue(char * &pVarname, double &value)
+bool findNextVariableValue(char * &pVarname, float &value)
 {
   bool succeed = true;
   value = 0;
@@ -854,12 +854,12 @@ bool findNextVariableValue(char * &pVarname, double &value)
   if (sVarName.startsWith(F("VAR"))) {
     int index = sVarName.substring(3).toInt();
     if (index > 0 && index <= MAX_RULE_VARS) {
-      value = CharToDouble(vars[index -1]);
+      value = CharToFloat(vars[index -1]);
     }
   } else if (sVarName.startsWith(F("MEM"))) {
     int index = sVarName.substring(3).toInt();
     if (index > 0 && index <= MAX_RULE_MEMS) {
-      value = CharToDouble(Settings.mems[index -1]);
+      value = CharToFloat(Settings.mems[index -1]);
     }
   } else if (sVarName.equals(F("TIME"))) {
     value = MinutesPastMidnight();
@@ -891,15 +891,15 @@ bool findNextVariableValue(char * &pVarname, double &value)
  *     - An expression enclosed with a pair of round brackets, (.....)
  * Input:
  *      pointer     - A char pointer point to a place of the expression string
- *      value       - Reference a double variable used to accept the result
+ *      value       - Reference a float variable used to accept the result
  * Output:
  *      pointer     - Pointer forward to next character after next object
- *      value       - double type, the result value
+ *      value       - float type, the result value
  * Return:
  *      true    - succeed
  *      false   - failed
  */
-bool findNextObjectValue(char * &pointer, double &value)
+bool findNextObjectValue(char * &pointer, float &value)
 {
   bool bSucceed = false;
   while (*pointer)
@@ -984,15 +984,15 @@ bool findNextOperator(char * &pointer, int8_t &op)
  * Calculate a simple expression composed by 2 value and 1 operator, like 2 * 3
  * Input:
  *      pointer     - A char pointer point to a place of the expression string
- *      value       - Reference a double variable used to accept the result
+ *      value       - Reference a float variable used to accept the result
  * Output:
  *      pointer     - Pointer forward to next character after next object
- *      value       - double type, the result value
+ *      value       - float type, the result value
  * Return:
  *      true    - succeed
  *      false   - failed
  */
-double calculateTwoValues(double v1, double v2, uint8_t op)
+float calculateTwoValues(float v1, float v2, uint8_t op)
 {
   switch (op)
   {
@@ -1025,7 +1025,7 @@ double calculateTwoValues(double v1, double v2, uint8_t op)
  *      expression  - The expression to be evaluated
  *      len         - Length of the expression
  * Return:
- *      double      - result.
+ *      float      - result.
  *      0           - if the expression is invalid
  * An example:
  * MEM1 = 3, MEM2 = 6, VAR2 = 15, VAR10 = 80
@@ -1045,17 +1045,17 @@ double calculateTwoValues(double v1, double v2, uint8_t op)
  *  2             +                                   1
  *  3             /                                   2
  */
-double evaluateExpression(const char * expression, unsigned int len)
+float evaluateExpression(const char * expression, unsigned int len)
 {
   char expbuf[len + 1];
   memcpy(expbuf, expression, len);
   expbuf[len] = '\0';
   char * scan_pointer = expbuf;
 
-  LinkedList<double> object_values;
+  LinkedList<float> object_values;
   LinkedList<int8_t> operators;
   int8_t op;
-  double va;
+  float va;
   //Find and add the value of first object
   if (findNextObjectValue(scan_pointer, va)) {
     object_values.add(va);
@@ -1154,7 +1154,7 @@ bool RulesCommand(void)
   else if ((CMND_RULETIMER == command_code) && (index > 0) && (index <= MAX_RULE_TIMERS)) {
     if (XdrvMailbox.data_len > 0) {
 #ifdef USE_EXPRESSION
-      double timer_set = evaluateExpression(XdrvMailbox.data, XdrvMailbox.data_len);
+      float timer_set = evaluateExpression(XdrvMailbox.data, XdrvMailbox.data_len);
       rules_timer[index -1] = (timer_set > 0) ? millis() + (1000 * timer_set) : 0;
 #else
       rules_timer[index -1] = (XdrvMailbox.payload > 0) ? millis() + (1000 * XdrvMailbox.payload) : 0;
@@ -1202,7 +1202,7 @@ bool RulesCommand(void)
   }
   else if ((CMND_ADD == command_code) && (index > 0) && (index <= MAX_RULE_VARS)) {
     if (XdrvMailbox.data_len > 0) {
-      double tempvar = CharToDouble(vars[index -1]) + CharToDouble(XdrvMailbox.data);
+      float tempvar = CharToFloat(vars[index -1]) + CharToFloat(XdrvMailbox.data);
       dtostrfd(tempvar, Settings.flag2.calc_resolution, vars[index -1]);
       bitSet(vars_event, index -1);
     }
@@ -1210,7 +1210,7 @@ bool RulesCommand(void)
   }
   else if ((CMND_SUB == command_code) && (index > 0) && (index <= MAX_RULE_VARS)) {
     if (XdrvMailbox.data_len > 0) {
-      double tempvar = CharToDouble(vars[index -1]) - CharToDouble(XdrvMailbox.data);
+      float tempvar = CharToFloat(vars[index -1]) - CharToFloat(XdrvMailbox.data);
       dtostrfd(tempvar, Settings.flag2.calc_resolution, vars[index -1]);
       bitSet(vars_event, index -1);
     }
@@ -1218,7 +1218,7 @@ bool RulesCommand(void)
   }
   else if ((CMND_MULT == command_code) && (index > 0) && (index <= MAX_RULE_VARS)) {
     if (XdrvMailbox.data_len > 0) {
-      double tempvar = CharToDouble(vars[index -1]) * CharToDouble(XdrvMailbox.data);
+      float tempvar = CharToFloat(vars[index -1]) * CharToFloat(XdrvMailbox.data);
       dtostrfd(tempvar, Settings.flag2.calc_resolution, vars[index -1]);
       bitSet(vars_event, index -1);
     }
@@ -1229,12 +1229,12 @@ bool RulesCommand(void)
       if (strstr(XdrvMailbox.data, ",") != nullptr) {  // Process parameter entry
         char sub_string[XdrvMailbox.data_len +1];
 
-        double valueIN = CharToDouble(subStr(sub_string, XdrvMailbox.data, ",", 1));
-        double fromLow = CharToDouble(subStr(sub_string, XdrvMailbox.data, ",", 2));
-        double fromHigh = CharToDouble(subStr(sub_string, XdrvMailbox.data, ",", 3));
-        double toLow = CharToDouble(subStr(sub_string, XdrvMailbox.data, ",", 4));
-        double toHigh = CharToDouble(subStr(sub_string, XdrvMailbox.data, ",", 5));
-        double value = map_double(valueIN, fromLow, fromHigh, toLow, toHigh);
+        float valueIN = CharToFloat(subStr(sub_string, XdrvMailbox.data, ",", 1));
+        float fromLow = CharToFloat(subStr(sub_string, XdrvMailbox.data, ",", 2));
+        float fromHigh = CharToFloat(subStr(sub_string, XdrvMailbox.data, ",", 3));
+        float toLow = CharToFloat(subStr(sub_string, XdrvMailbox.data, ",", 4));
+        float toHigh = CharToFloat(subStr(sub_string, XdrvMailbox.data, ",", 5));
+        float value = map_double(valueIN, fromLow, fromHigh, toLow, toHigh);
         dtostrfd(value, Settings.flag2.calc_resolution, vars[index -1]);
         bitSet(vars_event, index -1);
       }
@@ -1254,7 +1254,7 @@ bool RulesCommand(void)
   return serviced;
 }
 
-double map_double(double x, double in_min, double in_max, double out_min, double out_max)
+float map_double(float x, float in_min, float in_max, float out_min, float out_max)
 {
  return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
 }
@@ -1302,4 +1302,4 @@ bool Xdrv10(uint8_t function)
 }
 
 #endif  // Do not USE_SCRIPT
-#endif  // USE_RULES
\ No newline at end of file
+#endif  // USE_RULES
diff --git a/sonoff/xdrv_10_scripter.ino b/sonoff/xdrv_10_scripter.ino
index 93ff63878..284128033 100644
--- a/sonoff/xdrv_10_scripter.ino
+++ b/sonoff/xdrv_10_scripter.ino
@@ -298,7 +298,7 @@ char *script;
                 op++;
                 if (*op!='"') {
                     float fv;
-                    fv=CharToDouble(op);
+                    fv=CharToFloat(op);
                     fvalues[nvars]=fv;
                     vtypes[vars].bits.is_string=0;
                     if (!vtypes[vars].bits.is_filter) vtypes[vars].index=nvars;
@@ -670,7 +670,7 @@ char *isvar(char *lp, uint8_t *vtype,struct T_INDEX *tind,float *fp,char *sp,Jso
 
     if (isdigit(*lp) || (*lp=='-' && isdigit(*(lp+1))) || *lp=='.') {
       // isnumber
-        if (fp) *fp=CharToDouble(lp);
+        if (fp) *fp=CharToFloat(lp);
         if (*lp=='-') lp++;
         while (isdigit(*lp) || *lp=='.') {
           if (*lp==0 || *lp==SCRIPT_EOL) break;
@@ -839,7 +839,7 @@ char *isvar(char *lp, uint8_t *vtype,struct T_INDEX *tind,float *fp,char *sp,Jso
                 return lp+len;
               }
             } else {
-              if (fp) *fp=CharToDouble((char*)str_value);
+              if (fp) *fp=CharToFloat((char*)str_value);
               *vtype=NUM_RES;
               tind->bits.constant=1;
               tind->bits.is_string=0;
@@ -2266,7 +2266,7 @@ int16_t Run_Scripter(const char *type, uint8_t tlen, char *js) {
                   // mismatch was string, not number
                   // get the string and convert to number
                   lp=isvar(slp,&vtype,&ind,0,cmpstr,jo);
-                  fvar=CharToDouble(cmpstr);
+                  fvar=CharToFloat(cmpstr);
                 }
                 switch (lastop) {
                     case OPER_EQU:
@@ -2398,7 +2398,7 @@ int16_t Run_Scripter(const char *type, uint8_t tlen, char *js) {
                               *dfvar=fparam;
                             } else {
                               // mismatch
-                              *dfvar=CharToDouble(cmpstr);
+                              *dfvar=CharToFloat(cmpstr);
                             }
                         } else {
                             // string result
diff --git a/sonoff/xdrv_11_knx.ino b/sonoff/xdrv_11_knx.ino
index d0a2c9212..7a477bff8 100644
--- a/sonoff/xdrv_11_knx.ino
+++ b/sonoff/xdrv_11_knx.ino
@@ -1030,7 +1030,7 @@ bool KnxCommand(void)
     while ( i != KNX_Empty ) {
       KNX_addr.value = Settings.knx_GA_addr[i];
 
-      float tempvar = CharToDouble(XdrvMailbox.data);
+      float tempvar = CharToFloat(XdrvMailbox.data);
       dtostrfd(tempvar,2,XdrvMailbox.data);
 
       knx.write_2byte_float(KNX_addr, tempvar);
diff --git a/sonoff/xdrv_13_display.ino b/sonoff/xdrv_13_display.ino
index b00f2a3ce..c95fd980a 100644
--- a/sonoff/xdrv_13_display.ino
+++ b/sonoff/xdrv_13_display.ino
@@ -61,18 +61,8 @@ const char S_JSON_DISPLAY_COMMAND_VALUE[] PROGMEM =        "{\"" D_CMND_DISPLAY
 const char S_JSON_DISPLAY_COMMAND_NVALUE[] PROGMEM =       "{\"" D_CMND_DISPLAY "%s\":%d}";
 const char S_JSON_DISPLAY_COMMAND_INDEX_NVALUE[] PROGMEM = "{\"" D_CMND_DISPLAY "%s%d\":%d}";
 
-uint8_t disp_power = 0;
-uint8_t disp_device = 0;
-uint8_t disp_refresh = 1;
+char *dsp_str;
 
-int16_t disp_xpos = 0;
-int16_t disp_ypos = 0;
-uint8_t disp_autodraw = 1;
-
-uint8_t dsp_init;
-uint8_t dsp_font;
-uint8_t dsp_flag;
-uint8_t dsp_on;
 uint16_t dsp_x;
 uint16_t dsp_y;
 uint16_t dsp_x2;
@@ -80,21 +70,30 @@ uint16_t dsp_y2;
 uint16_t dsp_rad;
 uint16_t dsp_color;
 int16_t dsp_len;
-char *dsp_str;
+int16_t disp_xpos = 0;
+int16_t disp_ypos = 0;
+
+uint8_t disp_power = 0;
+uint8_t disp_device = 0;
+uint8_t disp_refresh = 1;
+uint8_t disp_autodraw = 1;
+uint8_t dsp_init;
+uint8_t dsp_font;
+uint8_t dsp_flag;
+uint8_t dsp_on;
 
 #ifdef USE_DISPLAY_MODES1TO5
 
-char disp_temp[2];    // C or F
-uint8_t disp_subscribed = 0;
-
 char **disp_log_buffer;
+char **disp_screen_buffer;
+char disp_temp[2];    // C or F
+
 uint8_t disp_log_buffer_cols = 0;
 uint8_t disp_log_buffer_idx = 0;
 uint8_t disp_log_buffer_ptr = 0;
-
-char **disp_screen_buffer;
 uint8_t disp_screen_buffer_cols = 0;
 uint8_t disp_screen_buffer_rows = 0;
+bool disp_subscribed = false;
 
 #endif  // USE_DISPLAY_MODES1TO5
 
@@ -820,8 +819,7 @@ void DisplayMqttSubscribe(void)
  * - home/%prefix%/%topic%
  * - home/level2/%prefix%/%topic% etc.
  */
-//  if (Settings.display_mode &0x04) {
-  if (Settings.display_model) {
+  if (Settings.display_model && (Settings.display_mode &0x04)) {
 
     char stopic[TOPSZ];
     char ntopic[TOPSZ];
@@ -839,9 +837,9 @@ void DisplayMqttSubscribe(void)
     strncat(ntopic, Settings.mqtt_prefix[2], sizeof(ntopic) - strlen(ntopic) -1);  // Subscribe to tele messages
     strncat_P(ntopic, PSTR("/#"), sizeof(ntopic) - strlen(ntopic) -1);             // Add multi-level wildcard
     MqttSubscribe(ntopic);
-    disp_subscribed = 1;
+    disp_subscribed = true;
   } else {
-    disp_subscribed = 0;
+    disp_subscribed = false;
   }
 }
 
@@ -948,16 +946,16 @@ bool DisplayCommand(void)
  * 5 = Mqtt up and time     Mqtt (incl local) sensors and time   Mqtt (incl local) sensors and time
 */
       if ((XdrvMailbox.payload >= 0) && (XdrvMailbox.payload <= 5)) {
-        uint8_t last_display_mode = Settings.display_mode;
+        uint32_t last_display_mode = Settings.display_mode;
         Settings.display_mode = XdrvMailbox.payload;
-        if (!disp_subscribed) {
+
+        if (disp_subscribed != (Settings.display_mode &0x04)) {
           restart_flag = 2;  // Restart to Add/Remove MQTT subscribe
         } else {
           if (last_display_mode && !Settings.display_mode) {  // Switch to mode 0
             DisplayInit(DISPLAY_INIT_MODE);
             DisplayClear();
           } else {
-//          if (!last_display_mode && Settings.display_mode) {  // Switch to non mode 0
             DisplayLogBufferInit();
             DisplayInit(DISPLAY_INIT_MODE);
           }
diff --git a/sonoff/xdsp_04_ili9341.ino b/sonoff/xdsp_04_ili9341.ino
index 5bb777607..f98866d5e 100644
--- a/sonoff/xdsp_04_ili9341.ino
+++ b/sonoff/xdsp_04_ili9341.ino
@@ -173,6 +173,7 @@ void Ili9341PrintLog(void)
           tft->print(disp_screen_buffer[i]);
           tft_scroll += theight;
           tft->setCursor(0, tft_scroll);
+          delay(1);  // Fix background runs heap usage due to long runtime of this loop (up to 1 second)
         }
         strlcpy(disp_screen_buffer[last_row], txt, disp_screen_buffer_cols);
         DisplayFillScreen(last_row);
diff --git a/sonoff/xnrg_01_hlw8012.ino b/sonoff/xnrg_01_hlw8012.ino
index 503d4e50f..73f31c91f 100644
--- a/sonoff/xnrg_01_hlw8012.ino
+++ b/sonoff/xnrg_01_hlw8012.ino
@@ -287,17 +287,17 @@ bool HlwCommand(void)
   }
   else if (CMND_POWERSET == energy_command_code) {
     if (XdrvMailbox.data_len && hlw_cf_power_pulse_length) {
-      Settings.energy_power_calibration = ((unsigned long)(CharToDouble(XdrvMailbox.data) * 10) * hlw_cf_power_pulse_length) / hlw_power_ratio;
+      Settings.energy_power_calibration = ((unsigned long)(CharToFloat(XdrvMailbox.data) * 10) * hlw_cf_power_pulse_length) / hlw_power_ratio;
     }
   }
   else if (CMND_VOLTAGESET == energy_command_code) {
     if (XdrvMailbox.data_len && hlw_cf1_voltage_pulse_length) {
-      Settings.energy_voltage_calibration = ((unsigned long)(CharToDouble(XdrvMailbox.data) * 10) * hlw_cf1_voltage_pulse_length) / hlw_voltage_ratio;
+      Settings.energy_voltage_calibration = ((unsigned long)(CharToFloat(XdrvMailbox.data) * 10) * hlw_cf1_voltage_pulse_length) / hlw_voltage_ratio;
     }
   }
   else if (CMND_CURRENTSET == energy_command_code) {
     if (XdrvMailbox.data_len && hlw_cf1_current_pulse_length) {
-      Settings.energy_current_calibration = ((unsigned long)(CharToDouble(XdrvMailbox.data)) * hlw_cf1_current_pulse_length) / hlw_current_ratio;
+      Settings.energy_current_calibration = ((unsigned long)(CharToFloat(XdrvMailbox.data)) * hlw_cf1_current_pulse_length) / hlw_current_ratio;
     }
   }
   else serviced = false;  // Unknown command
diff --git a/sonoff/xnrg_02_cse7766.ino b/sonoff/xnrg_02_cse7766.ino
index c546571bb..f9d6d81e2 100644
--- a/sonoff/xnrg_02_cse7766.ino
+++ b/sonoff/xnrg_02_cse7766.ino
@@ -225,17 +225,17 @@ bool CseCommand(void)
 
   if (CMND_POWERSET == energy_command_code) {
     if (XdrvMailbox.data_len && power_cycle) {
-      Settings.energy_power_calibration = (unsigned long)(CharToDouble(XdrvMailbox.data) * power_cycle) / CSE_PREF;
+      Settings.energy_power_calibration = (unsigned long)(CharToFloat(XdrvMailbox.data) * power_cycle) / CSE_PREF;
     }
   }
   else if (CMND_VOLTAGESET == energy_command_code) {
     if (XdrvMailbox.data_len && voltage_cycle) {
-      Settings.energy_voltage_calibration = (unsigned long)(CharToDouble(XdrvMailbox.data) * voltage_cycle) / CSE_UREF;
+      Settings.energy_voltage_calibration = (unsigned long)(CharToFloat(XdrvMailbox.data) * voltage_cycle) / CSE_UREF;
     }
   }
   else if (CMND_CURRENTSET == energy_command_code) {
     if (XdrvMailbox.data_len && current_cycle) {
-      Settings.energy_current_calibration = (unsigned long)(CharToDouble(XdrvMailbox.data) * current_cycle) / 1000;
+      Settings.energy_current_calibration = (unsigned long)(CharToFloat(XdrvMailbox.data) * current_cycle) / 1000;
     }
   }
   else serviced = false;  // Unknown command
diff --git a/sonoff/xnrg_04_mcp39f501.ino b/sonoff/xnrg_04_mcp39f501.ino
index 86bb81855..6171ef93a 100644
--- a/sonoff/xnrg_04_mcp39f501.ino
+++ b/sonoff/xnrg_04_mcp39f501.ino
@@ -604,7 +604,7 @@ bool McpCommand(void)
 
   if (CMND_POWERSET == energy_command_code) {
     if (XdrvMailbox.data_len && mcp_active_power) {
-      value = (unsigned long)(CharToDouble(XdrvMailbox.data) * 100);
+      value = (unsigned long)(CharToFloat(XdrvMailbox.data) * 100);
       if ((value > 100) && (value < 200000)) {  // Between 1W and 2000W
         Settings.energy_power_calibration = value;
         mcp_calibrate |= MCP_CALIBRATE_POWER;
@@ -614,7 +614,7 @@ bool McpCommand(void)
   }
   else if (CMND_VOLTAGESET == energy_command_code) {
     if (XdrvMailbox.data_len && mcp_voltage_rms) {
-      value = (unsigned long)(CharToDouble(XdrvMailbox.data) * 10);
+      value = (unsigned long)(CharToFloat(XdrvMailbox.data) * 10);
       if ((value > 1000) && (value < 2600)) {  // Between 100V and 260V
         Settings.energy_voltage_calibration = value;
         mcp_calibrate |= MCP_CALIBRATE_VOLTAGE;
@@ -624,7 +624,7 @@ bool McpCommand(void)
   }
   else if (CMND_CURRENTSET == energy_command_code) {
     if (XdrvMailbox.data_len && mcp_current_rms) {
-      value = (unsigned long)(CharToDouble(XdrvMailbox.data) * 10);
+      value = (unsigned long)(CharToFloat(XdrvMailbox.data) * 10);
       if ((value > 100) && (value < 80000)) {  // Between 10mA and 8A
         Settings.energy_current_calibration = value;
         mcp_calibrate |= MCP_CALIBRATE_CURRENT;
@@ -634,7 +634,7 @@ bool McpCommand(void)
   }
   else if (CMND_FREQUENCYSET == energy_command_code) {
     if (XdrvMailbox.data_len && mcp_line_frequency) {
-      value = (unsigned long)(CharToDouble(XdrvMailbox.data) * 1000);
+      value = (unsigned long)(CharToFloat(XdrvMailbox.data) * 1000);
       if ((value > 45000) && (value < 65000)) {  // Between 45Hz and 65Hz
         Settings.energy_frequency_calibration = value;
         mcp_calibrate |= MCP_CALIBRATE_FREQUENCY;
diff --git a/sonoff/xnrg_07_ade7953.ino b/sonoff/xnrg_07_ade7953.ino
index 09566266b..c11a283ae 100644
--- a/sonoff/xnrg_07_ade7953.ino
+++ b/sonoff/xnrg_07_ade7953.ino
@@ -184,7 +184,7 @@ bool Ade7953Command(void)
 {
   bool serviced = true;
 
-  uint32_t value = (uint32_t)(CharToDouble(XdrvMailbox.data) * 100);  // 1.23 = 123
+  uint32_t value = (uint32_t)(CharToFloat(XdrvMailbox.data) * 100);  // 1.23 = 123
 
   if (CMND_POWERCAL == energy_command_code) {
     if (1 == XdrvMailbox.payload) { XdrvMailbox.payload = ADE7953_PREF; }
diff --git a/sonoff/xsns_02_analog.ino b/sonoff/xsns_02_analog.ino
index 9a0c94029..6dbfcc53e 100644
--- a/sonoff/xsns_02_analog.ino
+++ b/sonoff/xsns_02_analog.ino
@@ -151,7 +151,7 @@ bool AdcCommand(void)
 //          Settings.adc_param_type = my_adc0;
           Settings.adc_param1 = strtol(subStr(sub_string, XdrvMailbox.data, ",", 2), nullptr, 10);
           Settings.adc_param2 = strtol(subStr(sub_string, XdrvMailbox.data, ",", 3), nullptr, 10);
-          Settings.adc_param3 = (int)(CharToDouble(subStr(sub_string, XdrvMailbox.data, ",", 4)) * 10000);
+          Settings.adc_param3 = (int)(CharToFloat(subStr(sub_string, XdrvMailbox.data, ",", 4)) * 10000);
         } else {                                         // Set default values based on current adc type
           // AdcParam 2
           // AdcParam 3
diff --git a/sonoff/xsns_34_hx711.ino b/sonoff/xsns_34_hx711.ino
index 47a38f7d3..8a362ddfd 100644
--- a/sonoff/xsns_34_hx711.ino
+++ b/sonoff/xsns_34_hx711.ino
@@ -204,7 +204,7 @@ bool HxCommand(void)
       break;
     case 6:  // WeightItem
       if (strstr(XdrvMailbox.data, ",") != nullptr) {
-        Settings.weight_item = (unsigned long)(CharToDouble(subStr(sub_string, XdrvMailbox.data, ",", 2)) * 10);
+        Settings.weight_item = (unsigned long)(CharToFloat(subStr(sub_string, XdrvMailbox.data, ",", 2)) * 10);
       }
       show_parms = true;
       break;
@@ -444,7 +444,7 @@ void HandleHxAction(void)
 
   if (WebServer->hasArg("calibrate")) {
     WebGetArg("p1", stemp1, sizeof(stemp1));
-    Settings.weight_reference = (!strlen(stemp1)) ? 0 : (unsigned long)(CharToDouble(stemp1) * 1000);
+    Settings.weight_reference = (!strlen(stemp1)) ? 0 : (unsigned long)(CharToFloat(stemp1) * 1000);
 
     HxLogUpdates();
 
@@ -471,7 +471,7 @@ void HxSaveSettings(void)
   char tmp[100];
 
   WebGetArg("p2", tmp, sizeof(tmp));
-  Settings.weight_item = (!strlen(tmp)) ? 0 : (unsigned long)(CharToDouble(tmp) * 10000);
+  Settings.weight_item = (!strlen(tmp)) ? 0 : (unsigned long)(CharToFloat(tmp) * 10000);
 
   HxLogUpdates();
 }
diff --git a/sonoff/xsns_38_az7798.ino b/sonoff/xsns_38_az7798.ino
index 9bf97a424..5339a392f 100644
--- a/sonoff/xsns_38_az7798.ino
+++ b/sonoff/xsns_38_az7798.ino
@@ -182,7 +182,7 @@ void AzEverySecond(void)
       return;
     }
     response_substr[j] = 0;                 // add null terminator
-    az_temperature = CharToDouble((char*)response_substr); // units (C or F) depends on meter setting
+    az_temperature = CharToFloat((char*)response_substr); // units (C or F) depends on meter setting
     if(az_response[i] == 'C') {             // meter transmits in degC
       az_temperature = ConvertTemp((float)az_temperature); // convert to degF, depending on settings
     } else {                                // meter transmits in degF
@@ -232,7 +232,7 @@ void AzEverySecond(void)
       return;
     }
     response_substr[j] = 0;                 // add null terminator
-    az_humidity = ConvertHumidity(CharToDouble((char*)response_substr));
+    az_humidity = ConvertHumidity(CharToFloat((char*)response_substr));
   }
 }