diff --git a/tools/esp_merge_bin.py b/tools/esp_merge_bin.py
index ade42435..342d2afe 100644
--- a/tools/esp_merge_bin.py
+++ b/tools/esp_merge_bin.py
@@ -34,6 +34,8 @@ def copy_merge_bins(source, target, env):
     flash_size = env.GetProjectOption("board_upload.flash_size")
 
     bootloader = "{}tools{}sdk{}esp32{}bin{}bootloader_dio_40m.bin".format(FRAMEWORK_DIR, os.path.sep, os.path.sep, os.path.sep, os.path.sep, os.path.sep)
+    if not os.path.isfile(bootloader):
+        bootloader = "{}tools{}sdk{}bin{}bootloader_dio_40m.bin".format(FRAMEWORK_DIR, os.path.sep, os.path.sep, os.path.sep, os.path.sep, os.path.sep)
     partitions = "{}{}partitions.bin".format(env.subst("$BUILD_DIR"), os.path.sep)
     boot_app0 = "{}tools{}partitions{}boot_app0.bin".format(FRAMEWORK_DIR, os.path.sep, os.path.sep, os.path.sep)
     firmware_dst ="{}firmware{}{}_full_{}_{}.bin".format(OUTPUT_DIR, os.path.sep, name, flash_size, version)