diff --git a/Marlin/src/module/temperature.cpp b/Marlin/src/module/temperature.cpp
index 4fe71d3fef..531c52c09d 100644
--- a/Marlin/src/module/temperature.cpp
+++ b/Marlin/src/module/temperature.cpp
@@ -2709,13 +2709,15 @@ void Temperature::init() {
 
   #if HAS_HOTEND
     #define _TEMP_MIN_E(NR) do{ \
-      const celsius_t tmin = _MAX(HEATER_##NR##_MINTEMP, TERN(TEMP_SENSOR_##NR##_IS_CUSTOM, 0, (int)pgm_read_word(&TEMPTABLE_##NR [TEMP_SENSOR_##NR##_MINTEMP_IND].celsius))); \
+      const celsius_t tmin_tmp = TERN(TEMP_SENSOR_##NR##_IS_CUSTOM, 0, int16_t(pgm_read_word(&TEMPTABLE_##NR [TEMP_SENSOR_##NR##_MINTEMP_IND].celsius))), \
+                      tmin = _MAX(HEATER_##NR##_MINTEMP, tmin_tmp); \
       temp_range[NR].mintemp = tmin; \
       while (analog_to_celsius_hotend(temp_range[NR].raw_min, NR) < tmin) \
         temp_range[NR].raw_min += TEMPDIR(NR) * (OVERSAMPLENR); \
     }while(0)
     #define _TEMP_MAX_E(NR) do{ \
-      const celsius_t tmax = _MIN(HEATER_##NR##_MAXTEMP, TERN(TEMP_SENSOR_##NR##_IS_CUSTOM, 2000, (int)pgm_read_word(&TEMPTABLE_##NR [TEMP_SENSOR_##NR##_MAXTEMP_IND].celsius) - 1)); \
+      const celsius_t tmax_tmp = TERN(TEMP_SENSOR_##NR##_IS_CUSTOM, 2000, int16_t(pgm_read_word(&TEMPTABLE_##NR [TEMP_SENSOR_##NR##_MAXTEMP_IND].celsius)) - 1), \
+                      tmax = _MIN(HEATER_##NR##_MAXTEMP, tmax_tmp); \
       temp_range[NR].maxtemp = tmax; \
       while (analog_to_celsius_hotend(temp_range[NR].raw_max, NR) > tmax) \
         temp_range[NR].raw_max -= TEMPDIR(NR) * (OVERSAMPLENR); \