diff --git a/label_printer_gui.py b/label_printer_gui.py
index b02f671..495f24b 100644
--- a/label_printer_gui.py
+++ b/label_printer_gui.py
@@ -19,6 +19,7 @@ from kivy.graphics import Color, Rectangle
 import os
 import threading
 import platform
+import time
 from print_label import print_label_standalone, get_available_printers
 from kivy.clock import Clock
 
@@ -36,11 +37,50 @@ class LabelPrinterApp(App):
     def __init__(self, **kwargs):
         super().__init__(**kwargs)
         self.available_printers = self.get_available_printers()
+        # Clean old PDF backup files on startup
+        self.cleanup_old_pdfs()
     
     def get_available_printers(self):
         """Get list of available printers (cross-platform)"""
         return get_available_printers()
     
+    def cleanup_old_pdfs(self, days=5):
+        """
+        Delete PDF files older than specified days from pdf_backup folder.
+        
+        Args:
+            days (int): Delete files older than this many days (default: 5)
+        """
+        pdf_backup_dir = 'pdf_backup'
+        
+        # Create folder if it doesn't exist
+        if not os.path.exists(pdf_backup_dir):
+            os.makedirs(pdf_backup_dir, exist_ok=True)
+            return
+        
+        try:
+            current_time = time.time()
+            cutoff_time = current_time - (days * 24 * 3600)  # Convert days to seconds
+            
+            for filename in os.listdir(pdf_backup_dir):
+                file_path = os.path.join(pdf_backup_dir, filename)
+                
+                # Only process PDF files
+                if not filename.endswith('.pdf'):
+                    continue
+                
+                # Check if file is older than cutoff
+                if os.path.isfile(file_path):
+                    file_mtime = os.path.getmtime(file_path)
+                    if file_mtime < cutoff_time:
+                        try:
+                            os.remove(file_path)
+                            print(f"Deleted old PDF: {filename}")
+                        except Exception as e:
+                            print(f"Failed to delete {filename}: {e}")
+        except Exception as e:
+            print(f"Error during PDF cleanup: {e}")
+    
     def build(self):
         """Build the simplified single-column UI"""
         self.title = "Label Printing"
@@ -212,7 +252,7 @@ class LabelPrinterApp(App):
                     # Use Clock.schedule_once to update UI from main thread
                     Clock.schedule_once(lambda dt: popup.dismiss(), 0)
                     Clock.schedule_once(lambda dt: self.show_popup("Success", "Label printed successfully!"), 0.1)
-                    # Clear inputs after successful print
+                    # Clear inputs after successful print (but keep printer selection)
                     Clock.schedule_once(lambda dt: self.clear_inputs(), 0.2)
                 else:
                     Clock.schedule_once(lambda dt: popup.dismiss(), 0)
@@ -226,10 +266,11 @@ class LabelPrinterApp(App):
         thread.start()
     
     def clear_inputs(self):
-        """Clear all input fields"""
+        """Clear only the input fields, preserving printer selection"""
         self.sap_input.text = ''
         self.qty_input.text = ''
         self.cable_id_input.text = ''
+        # Printer selection is NOT cleared - it persists until user changes it
     
     def show_popup(self, title, message):
         """Show a popup message"""