diff --git a/src/libslic3r/GCode/CoolingBuffer.cpp b/src/libslic3r/GCode/CoolingBuffer.cpp
index edb5b67915..812e71f714 100644
--- a/src/libslic3r/GCode/CoolingBuffer.cpp
+++ b/src/libslic3r/GCode/CoolingBuffer.cpp
@@ -736,8 +736,8 @@ std::string CoolingBuffer::apply_layer_cooldown(
     int  supp_interface_fan_speed = 0;
     auto change_extruder_set_fan = [ this, layer_id, layer_time, &new_gcode, &overhang_fan_control, &overhang_fan_speed, &supp_interface_fan_control, &supp_interface_fan_speed](bool immediately_apply) {
 #define EXTRUDER_CONFIG(OPT) m_config.OPT.get_at(m_current_extruder)
-        int fan_min_speed = EXTRUDER_CONFIG(fan_min_speed);
-        int fan_speed_new = EXTRUDER_CONFIG(reduce_fan_stop_start_freq) ? fan_min_speed : 0;
+        float fan_min_speed = EXTRUDER_CONFIG(fan_min_speed);
+        float fan_speed_new = EXTRUDER_CONFIG(reduce_fan_stop_start_freq) ? fan_min_speed : 0;
         //BBS
         int additional_fan_speed_new = EXTRUDER_CONFIG(additional_cooling_fan_speed);
         int close_fan_the_first_x_layers = EXTRUDER_CONFIG(close_fan_the_first_x_layers);
@@ -751,7 +751,7 @@ std::string CoolingBuffer::apply_layer_cooldown(
             close_fan_the_first_x_layers = 1;
         }
         if (int(layer_id) >= close_fan_the_first_x_layers) {
-            int   fan_max_speed             = EXTRUDER_CONFIG(fan_max_speed);
+            float   fan_max_speed             = EXTRUDER_CONFIG(fan_max_speed);
             float slow_down_layer_time = float(EXTRUDER_CONFIG(slow_down_layer_time));
             float fan_cooling_layer_time      = float(EXTRUDER_CONFIG(fan_cooling_layer_time));
             //BBS: always enable the fan speed interpolation according to layer time
diff --git a/src/libslic3r/PrintConfig.cpp b/src/libslic3r/PrintConfig.cpp
index c7281cdd3b..b9e2707522 100644
--- a/src/libslic3r/PrintConfig.cpp
+++ b/src/libslic3r/PrintConfig.cpp
@@ -2702,7 +2702,7 @@ def = this->add("filament_loading_speed", coFloats);
     def->mode = comAdvanced;
     def->set_default_value(new ConfigOptionFloats{ 0., 0. });
 
-    def = this->add("fan_max_speed", coInts);
+    def = this->add("fan_max_speed", coFloats);
     def->label = L("Fan speed");
     def->tooltip = L("Part cooling fan speed may be increased when auto cooling is enabled. "
                      "This is the maximum speed limitation of part cooling fan");
@@ -2710,7 +2710,7 @@ def = this->add("filament_loading_speed", coFloats);
     def->min = 0;
     def->max = 100;
     def->mode = comSimple;
-    def->set_default_value(new ConfigOptionInts { 100 });
+    def->set_default_value(new ConfigOptionFloats { 100 });
 
     def = this->add("max_layer_height", coFloats);
     def->label = L("Max");
@@ -2753,14 +2753,14 @@ def = this->add("filament_loading_speed", coFloats);
     def->mode = comAdvanced;
     def->set_default_value(new ConfigOptionInt(3));
 
-    def = this->add("fan_min_speed", coInts);
+    def = this->add("fan_min_speed", coFloats);
     def->label = L("Fan speed");
     def->tooltip = L("Minimum speed for part cooling fan");
     def->sidetext = L("%");
     def->min = 0;
     def->max = 100;
     def->mode = comSimple;
-    def->set_default_value(new ConfigOptionInts { 20 });
+    def->set_default_value(new ConfigOptionFloats { 20 });
 
     def = this->add("additional_cooling_fan_speed", coInts);
     def->label = L("Fan speed");
diff --git a/src/libslic3r/PrintConfig.hpp b/src/libslic3r/PrintConfig.hpp
index 8d63e543ae..662b323b9b 100644
--- a/src/libslic3r/PrintConfig.hpp
+++ b/src/libslic3r/PrintConfig.hpp
@@ -1098,9 +1098,9 @@ PRINT_CONFIG_CLASS_DERIVED_DEFINE(
     ((ConfigOptionFloat,              initial_layer_infill_speed))
     ((ConfigOptionInts,               nozzle_temperature_initial_layer))
     ((ConfigOptionInts,               full_fan_speed_layer))
-    ((ConfigOptionInts,               fan_max_speed))
+    ((ConfigOptionFloats,               fan_max_speed))
     ((ConfigOptionFloats,             max_layer_height))
-    ((ConfigOptionInts,               fan_min_speed))
+    ((ConfigOptionFloats,               fan_min_speed))
     ((ConfigOptionFloats,             min_layer_height))
     ((ConfigOptionFloat,              printable_height))
     ((ConfigOptionPoint,              best_object_pos))