diff --git a/routes/auth.py b/routes/auth.py
index e2560cd..1434f07 100644
--- a/routes/auth.py
+++ b/routes/auth.py
@@ -141,7 +141,7 @@ def login():
                     )
 
                 flash(f'Welcome back, {user.full_name}!', 'success')
-                print(f"User {user.username} logged in successfully")
+                logger_handler.logger.info(f"User {user.username} (ID: {user.id}) logged in successfully")
 
                 # Redirect to intended page or dashboard
                 next_page = request.args.get('next')
@@ -158,11 +158,11 @@ def login():
                 )
 
                 flash('Invalid username or password.', 'error')
-                print(f"Failed login attempt for username: {username}")
+                logger_handler.logger.warning(f"Failed login attempt for username: {username}")
 
         except Exception as e:
             logger_handler.log_database_error('user_login', e)
-            print(f"Login error: {e}")
+            logger_handler.logger.error(f"Login error for username '{username}': {e}")
             flash('Login error. Please try again.', 'error')
 
     return render_template('login.html')
@@ -261,4 +261,4 @@ def profile():
     except Exception as e:
         logger_handler.log_database_error('profile_update', e)
         flash('Profile update failed. Please try again.', 'error')
-        return redirect(url_for('dashboard.dashboard'))
+        return redirect(url_for('dashboard.dashboard'))
\ No newline at end of file
diff --git a/routes/employees.py b/routes/employees.py
index 52dc667..aabfdd6 100644
--- a/routes/employees.py
+++ b/routes/employees.py
@@ -32,11 +32,7 @@ bp = Blueprint('employees', __name__)
 def employees():
     """Display employee management page with search and pagination"""
     try:
-        # Log user accessing employee management
-        try:
-            logger_handler.logger.info(f"User {session['username']} accessed employee management list")
-        except Exception as log_error:
-            print(f"⚠️ Logging error (non-critical): {log_error}")
+        logger_handler.logger.info(f"User {session['username']} accessed employee management list")
         
         # Get search parameters
         search = request.args.get('search', '').strip()
@@ -138,12 +134,12 @@ def create_employee():
             db.session.commit()
             
             # Log employee creation with project info
-            try:
-                project = Project.query.get(contract_id_int)
-                project_name = project.name if project else f"Project {contract_id_int}"
-                logger_handler.logger.info(f"Admin user {session['username']} created new employee: {employee_id_int} - {first_name} {last_name} assigned to {project_name}")
-            except Exception as log_error:
-                print(f"⚠️ Logging error (non-critical): {log_error}")
+            project = Project.query.get(contract_id_int)
+            project_name = project.name if project else f"Project {contract_id_int}"
+            logger_handler.logger.info(
+                f"User {session['username']} created new employee: "
+                f"{employee_id_int} - {first_name} {last_name} assigned to {project_name}"
+            )
             
             flash(f'Employee "{first_name} {last_name}" (ID: {employee_id}) created successfully.', 'success')
             return redirect(url_for('employees.employees'))
@@ -215,14 +211,14 @@ def edit_employee(employee_index):
             employee.contractId = contract_id_int
             
             db.session.commit()
-            
+
             # Log employee update with project info
-            try:
-                project = Project.query.get(contract_id_int)
-                project_name = project.name if project else f"Project {contract_id_int}"
-                logger_handler.logger.info(f"Admin user {session['username']} updated employee: {employee_index} - {first_name} {last_name} assigned to {project_name}")
-            except Exception as log_error:
-                print(f"⚠️ Logging error (non-critical): {log_error}")
+            project = Project.query.get(contract_id_int)
+            project_name = project.name if project else f"Project {contract_id_int}"
+            logger_handler.logger.info(
+                f"User {session['username']} updated employee: "
+                f"{employee_index} - {first_name} {last_name} assigned to {project_name}"
+            )
             
             flash(f'Employee "{first_name} {last_name}" updated successfully.', 'success')
             return redirect(url_for('employees.employees'))
@@ -241,16 +237,15 @@ def edit_employee(employee_index):
 @login_required
 @log_database_operations('employee_deletion')
 def delete_employee(employee_index):
-    """Delete employee (Admin only) - Enhanced with better logging"""
+    """Delete employee (Admin only)"""
     try:
-        print(f"🗑️ DELETE REQUEST: Employee index {employee_index}")
-        print(f"📋 Request method: {request.method}")
-        print(f"👤 User: {session.get('username', 'Unknown')}")
-        
+        logger_handler.logger.info(
+            f"User {session.get('username', 'Unknown')} initiated delete for employee index {employee_index}"
+        )
+
         # Get employee by index (primary key)
         employee = Employee.query.get_or_404(employee_index)
-        print(f"✅ Found employee: {employee.firstName} {employee.lastName} (ID: {employee.id})")
-        
+
         # Store employee data for logging before deletion
         employee_data = {
             'index': employee.index,
@@ -260,44 +255,42 @@ def delete_employee(employee_index):
             'title': employee.title,
             'contractId': employee.contractId
         }
-        
+
         # Check if employee has attendance records
         attendance_count = AttendanceData.query.filter_by(employee_id=str(employee.id)).count()
-        print(f"📊 Attendance records found: {attendance_count}")
-        
+
         if attendance_count > 0:
-            error_msg = f'Cannot delete employee "{employee.full_name}". Employee has {attendance_count} attendance records. Please contact system administrator.'
-            print(f"❌ DELETION BLOCKED: {error_msg}")
+            error_msg = (
+                f'Cannot delete employee "{employee.full_name}". '
+                f'Employee has {attendance_count} attendance records. '
+                f'Please contact system administrator.'
+            )
+            logger_handler.logger.warning(
+                f"Deletion blocked for employee {employee_data['id']} "
+                f"({employee_data['firstName']} {employee_data['lastName']}): "
+                f"{attendance_count} attendance records exist"
+            )
             flash(error_msg, 'error')
             return redirect(url_for('employees.employees'))
-        
-        # Proceed with deletion
-        print(f"🗑️ Proceeding with deletion of employee: {employee_data['firstName']} {employee_data['lastName']}")
-        
+
         db.session.delete(employee)
         db.session.commit()
-        print("✅ Employee successfully deleted from database")
-        
-        # Log employee deletion
-        try:
-            logger_handler.logger.info(f"Admin user {session['username']} deleted employee: {employee_data['firstName']} {employee_data['lastName']} (ID: {employee_data['id']})")
-            print(f"📋 Deletion logged successfully")
-        except Exception as log_error:
-            print(f"⚠️ Logging error (non-critical): {log_error}")
-        
-        success_msg = f'Employee "{employee_data["firstName"]} {employee_data["lastName"]}" deleted successfully.'
-        flash(success_msg, 'success')
-        print(f"✅ SUCCESS: {success_msg}")
-        
+
+        logger_handler.logger.info(
+            f"User {session['username']} deleted employee: "
+            f"{employee_data['firstName']} {employee_data['lastName']} (ID: {employee_data['id']})"
+        )
+
+        flash(
+            f'Employee "{employee_data["firstName"]} {employee_data["lastName"]}" deleted successfully.',
+            'success'
+        )
         return redirect(url_for('employees.employees'))
-        
+
     except Exception as e:
         db.session.rollback()
         logger_handler.log_database_error('employee_deletion', e)
-        error_msg = f'Error deleting employee. Please try again.'
-        print(f"❌ ERROR in delete_employee: {e}")
-        print(f"❌ Exception type: {type(e)}")
-        flash(error_msg, 'error')
+        flash('Error deleting employee. Please try again.', 'error')
         return redirect(url_for('employees.employees'))
 
 @bp.route('/api/employees/search', endpoint='api_employees_search')
@@ -368,10 +361,9 @@ def employee_detail(employee_index):
         }
         
         # Log employee detail view
-        try:
-            logger_handler.logger.info(f"User {session['username']} viewed employee detail: {employee.full_name} (ID: {employee.id})")
-        except Exception as log_error:
-            print(f"⚠️ Logging error (non-critical): {log_error}")
+        logger_handler.logger.info(
+            f"User {session['username']} viewed employee detail: {employee.full_name} (ID: {employee.id})"
+        )
         
         return render_template('employee_detail.html', 
                              employee=employee, 
@@ -380,4 +372,4 @@ def employee_detail(employee_index):
     except Exception as e:
         logger_handler.log_database_error('employee_detail', e)
         flash('Error loading employee details. Please try again.', 'error')
-        return redirect(url_for('employees.employees'))
+        return redirect(url_for('employees.employees'))
\ No newline at end of file
diff --git a/routes/users.py b/routes/users.py
index cb20261..197d0a4 100644
--- a/routes/users.py
+++ b/routes/users.py
@@ -201,21 +201,6 @@ def create_user():
         flash('Error loading form. Please try again.', 'error')
         return redirect(url_for('users.users'))
 
-def get_all_locations_from_qr_codes():
-    """Helper function to get all unique locations from QR codes"""
-    try:
-        result = db.session.execute(text("""
-            SELECT DISTINCT location 
-            FROM qr_codes 
-            WHERE location IS NOT NULL 
-            AND active_status = 1
-            ORDER BY location
-        """))
-        return [row[0] for row in result.fetchall()]
-    except Exception as e:
-        logger_handler.logger.error(f"Error loading locations: {e}")
-        return []
-    
 @bp.route('/users/<int:user_id>/delete', methods=['GET', 'POST'], endpoint='delete_user')
 @admin_required
 def delete_user(user_id):
@@ -244,14 +229,16 @@ def delete_user(user_id):
         user_to_delete.active_status = False
         db.session.commit()
 
+        logger_handler.logger.info(
+            f"Admin {current_user.username} deactivated user: {user_to_delete.username} (ID: {user_to_delete.id})"
+        )
         flash(f'User "{user_to_delete.full_name}" has been deactivated successfully.', 'success')
-        print(f"Admin {current_user.username} deactivated user: {user_to_delete.username}")
 
         return redirect(url_for('users.users'))
 
     except Exception as e:
         db.session.rollback()
-        print(f"Error deactivating user: {e}")
+        logger_handler.log_database_error('user_deactivation', e)
         flash('Error deactivating user. Please try again.', 'error')
         return redirect(url_for('users.users'))
 
@@ -272,14 +259,16 @@ def reactivate_user(user_id):
         else:
             user_to_reactivate.active_status = True
             db.session.commit()
+            logger_handler.logger.info(
+                f"Admin {current_user.username} reactivated user: {user_to_reactivate.username} (ID: {user_to_reactivate.id})"
+            )
             flash(f'User "{user_to_reactivate.full_name}" has been reactivated successfully.', 'success')
-            print(f"Admin {current_user.username} reactivated user: {user_to_reactivate.username}")
 
         return redirect(url_for('users.users'))
 
     except Exception as e:
         db.session.rollback()
-        print(f"Error reactivating user: {e}")
+        logger_handler.log_database_error('user_reactivation', e)
         flash('Error reactivating user. Please try again.', 'error')
         return redirect(url_for('users.users'))
 
@@ -300,14 +289,16 @@ def promote_user(user_id):
         else:
             user_to_promote.role = 'admin'
             db.session.commit()
+            logger_handler.logger.info(
+                f"Admin {current_user.username} promoted user {user_to_promote.username} (ID: {user_to_promote.id}) to admin"
+            )
             flash(f'"{user_to_promote.full_name}" has been promoted to admin.', 'success')
-            print(f"Admin {current_user.username} promoted user {user_to_promote.username} to admin")
 
         return redirect(url_for('users.users'))
 
     except Exception as e:
         db.session.rollback()
-        print(f"Error promoting user: {e}")
+        logger_handler.log_database_error('user_promotion', e)
         flash('Error promoting user. Please try again.', 'error')
         return redirect(url_for('users.users'))
 
@@ -339,14 +330,16 @@ def demote_user(user_id):
         else:
             user_to_demote.role = 'staff'
             db.session.commit()
+            logger_handler.logger.info(
+                f"Admin {current_user.username} demoted user {user_to_demote.username} (ID: {user_to_demote.id}) to staff"
+            )
             flash(f'"{user_to_demote.full_name}" has been demoted to staff.', 'success')
-            print(f"Admin {current_user.username} demoted user {user_to_demote.username} to staff")
 
         return redirect(url_for('users.users'))
 
     except Exception as e:
         db.session.rollback()
-        print(f"Error demoting user: {e}")
+        logger_handler.log_database_error('user_demotion', e)
         flash('Error demoting user. Please try again.', 'error')
         return redirect(url_for('users.users'))
 
@@ -602,9 +595,9 @@ def toggle_user_status(user_id):
         message = f'"{user_to_toggle.full_name}" has been {action} successfully.'
 
         # Log status change
-        logger_handler.logger.info(f"Admin {current_user.username} {action} user {user_to_toggle.username}")
-
-        print(f"Admin {current_user.username} {action} user {user_to_toggle.username}")
+        logger_handler.logger.info(
+            f"Admin {current_user.username} {action} user {user_to_toggle.username} (ID: {user_to_toggle.id})"
+        )
 
         return jsonify({
             'success': True,
@@ -616,7 +609,6 @@ def toggle_user_status(user_id):
     except Exception as e:
         db.session.rollback()
         logger_handler.log_database_error('user_status_toggle', e)
-        print(f"Error toggling user status: {e}")
         return jsonify({
             'success': False,
             'message': 'Error updating user status. Please try again.'
@@ -641,17 +633,17 @@ def activate_user(user_id):
             db.session.commit()
 
             # Log activation
-            logger_handler.logger.info(f"Admin {current_user.username} activated user {user_to_activate.username}")
+            logger_handler.logger.info(
+                f"Admin {current_user.username} activated user {user_to_activate.username} (ID: {user_to_activate.id})"
+            )
 
             flash(f'"{user_to_activate.full_name}" has been activated.', 'success')
-            print(f"Admin {current_user.username} activated user {user_to_activate.username}")
 
         return redirect(url_for('users.users'))
 
     except Exception as e:
         db.session.rollback()
         logger_handler.log_database_error('user_activation', e)
-        print(f"Error activating user: {e}")
         flash('Error activating user. Please try again.', 'error')
         return redirect(url_for('users.users'))
 
@@ -686,17 +678,17 @@ def deactivate_user(user_id):
             db.session.commit()
 
             # Log deactivation
-            logger_handler.logger.info(f"Admin {current_user.username} deactivated user {user_to_deactivate.username}")
+            logger_handler.logger.info(
+                f"Admin {current_user.username} deactivated user {user_to_deactivate.username} (ID: {user_to_deactivate.id})"
+            )
 
             flash(f'"{user_to_deactivate.full_name}" has been deactivated.', 'success')
-            print(f"Admin {current_user.username} deactivated user {user_to_deactivate.username}")
 
         return redirect(url_for('users.users'))
 
     except Exception as e:
         db.session.rollback()
         logger_handler.log_database_error('user_deactivation', e)
-        print(f"Error deactivating user: {e}")
         flash('Error deactivating user. Please try again.', 'error')
         return redirect(url_for('users.users'))
 
@@ -741,7 +733,6 @@ def user_stats_api():
 
     except Exception as e:
         logger_handler.log_database_error('user_stats_api', e)
-        print(f"Error fetching user stats: {e}")
         return jsonify({'error': 'Failed to fetch user statistics'}), 500
     
 @bp.route('/api/locations-by-projects', methods=['POST'], endpoint='get_locations_by_projects')
@@ -802,7 +793,7 @@ def role_permissions_api():
         })
 
     except Exception as e:
-        print(f"Error fetching role permissions: {e}")
+        logger_handler.log_database_error('role_permissions_api', e)
         return jsonify({'error': 'Failed to fetch role permissions'}), 500
 
 @bp.route('/api/geocode', methods=['POST'], endpoint='geocode_address_api')
@@ -820,20 +811,16 @@ def geocode_address_api():
             }), 400
 
         # Log API geocoding request
-        try:
-            logger_handler.log_user_activity('api_geocoding_request', f'API geocoding request: {address[:50]}...')
-        except Exception as log_error:
-            print(f"⚠️ Logging error (non-critical): {log_error}")
+        logger_handler.logger.info(f"API geocoding request from user {session.get('username', 'unknown')}: {address[:50]}")
 
         # Use the enhanced function that returns 3 values
         lat, lng, accuracy = get_coordinates_from_address_enhanced(address)
 
         if lat is not None and lng is not None:
-            # Log successful API geocoding
-            try:
-                logger_handler.log_user_activity('api_geocoding_success', f'API geocoding success: {address[:50]}... -> {lat}, {lng} ({accuracy})')
-            except Exception as log_error:
-                print(f"⚠️ Logging error (non-critical): {log_error}")
+            logger_handler.logger.info(
+                f"API geocoding success for user {session.get('username', 'unknown')}: "
+                f"{address[:50]} -> {lat}, {lng} ({accuracy})"
+            )
 
             return jsonify({
                 'success': True,
@@ -847,11 +834,9 @@ def geocode_address_api():
                 'message': f'Address geocoded successfully with {accuracy} accuracy using {"Google Maps" if gmaps_client else "OpenStreetMap"}'
             })
         else:
-            # Log failed API geocoding
-            try:
-                logger_handler.log_user_activity('api_geocoding_failed', f'API geocoding failed: {address[:50]}...')
-            except Exception as log_error:
-                print(f"⚠️ Logging error (non-critical): {log_error}")
+            logger_handler.logger.warning(
+                f"API geocoding failed for user {session.get('username', 'unknown')}: {address[:50]}"
+            )
 
             return jsonify({
                 'success': False,
@@ -859,13 +844,7 @@ def geocode_address_api():
             }), 404
 
     except Exception as e:
-        print(f"❌ Geocoding API error: {e}")
-        
-        # Log API geocoding error
-        try:
-            logger_handler.log_flask_error('api_geocoding_error', f'API geocoding error: {str(e)}')
-        except Exception as log_error:
-            print(f"⚠️ Logging error (non-critical): {log_error}")
+        logger_handler.log_flask_error('api_geocoding_error', f'API geocoding error: {str(e)}')
 
         return jsonify({
             'success': False,
@@ -888,10 +867,9 @@ def reverse_geocode_api():
             }), 400
 
         # Log API reverse geocoding request
-        try:
-            logger_handler.log_user_activity('api_reverse_geocoding_request', f'API reverse geocoding: {latitude}, {longitude}')
-        except Exception as log_error:
-            print(f"⚠️ Logging error (non-critical): {log_error}")
+        logger_handler.logger.info(
+            f"API reverse geocoding request from user {session.get('username', 'unknown')}: {latitude}, {longitude}"
+        )
 
         # Use the reverse geocoding function
         address = reverse_geocode_coordinates(latitude, longitude)
@@ -913,13 +891,7 @@ def reverse_geocode_api():
             }), 404
 
     except Exception as e:
-        print(f"❌ Reverse geocoding API error: {e}")
-        
-        # Log API reverse geocoding error
-        try:
-            logger_handler.log_flask_error('api_reverse_geocoding_error', f'API reverse geocoding error: {str(e)}')
-        except Exception as log_error:
-            print(f"⚠️ Logging error (non-critical): {log_error}")
+        logger_handler.log_flask_error('api_reverse_geocoding_error', f'API reverse geocoding error: {str(e)}')
 
         return jsonify({
             'success': False,
@@ -977,16 +949,21 @@ def permanently_delete_user(user_id):
         db.session.delete(user_to_delete)
         db.session.commit()
 
-        # Updated flash message to reflect QR codes are preserved
-        flash(f'User "{user_name}" has been permanently deleted. {user_qr_count} QR codes created by this user are now orphaned but preserved.', 'success')
-        print(f"Admin {current_user.username} permanently deleted user: {username}, preserved {user_qr_count} QR codes")
+        logger_handler.logger.info(
+            f"Admin {current_user.username} permanently deleted user: {username}, "
+            f"preserved {user_qr_count} QR codes"
+        )
+        flash(
+            f'User "{user_name}" has been permanently deleted. '
+            f'{user_qr_count} QR codes created by this user are now orphaned but preserved.',
+            'success'
+        )
 
         return redirect(url_for('users.users'))
 
     except Exception as e:
         db.session.rollback()
         logger_handler.log_database_error('user_permanent_deletion', e)
-        print(f"Error permanently deleting user: {e}")
         flash('Error deleting user. Please try again.', 'error')
         return redirect(url_for('users.users'))
 
diff --git a/working_hours_calculator.py b/working_hours_calculator.py
index b130c50..1212a6a 100644
--- a/working_hours_calculator.py
+++ b/working_hours_calculator.py
@@ -23,8 +23,11 @@ from typing import List, Dict, Optional, Tuple, Any
 from dataclasses import dataclass
 import math
 import re
+import logging
 from logger_handler import log_database_operations
 
+_calc_logger = logging.getLogger('qr_attendance_app')
+
 # Constants from Java implementation
 RECORD_GROUPING_MAX_MINUTES = 60 * 6  # 6 hours
 MAX_REGULAR_TIME_MINUTES = 60 * 40    # 40 hours per week
@@ -402,7 +405,7 @@ class WorkingHoursCalculator:
             Dictionary containing daily and weekly hour calculations with SP/PW/PT breakdown
         """
         try:
-            print(f"🔍 Calculating hours for base employee {employee_id} with SP/PW/PT support")
+            _calc_logger.debug(f"Calculating hours for base employee {employee_id} with SP/PW/PT support")
             
             # Parse base employee ID
             base_employee_id, _ = parse_employee_id_for_work_type(employee_id)
@@ -460,11 +463,15 @@ class WorkingHoursCalculator:
                         records_by_type[work_type].append(att_record)
                         
                 except Exception as record_error:
-                    print(f"⚠️ Error processing record: {record_error}")
+                    _calc_logger.warning(f"Error processing attendance record: {record_error}")
                     continue
             
             total_records = sum(len(records_by_type[wt]) for wt in records_by_type)
-            print(f"📊 Found {total_records} records - Regular: {len(records_by_type['regular'])}, SP: {len(records_by_type['SP'])}, PW: {len(records_by_type['PW'])}, PT: {len(records_by_type['PT'])}")
+            _calc_logger.debug(
+                f"Employee {employee_id}: {total_records} records found — "
+                f"Regular: {len(records_by_type['regular'])}, SP: {len(records_by_type['SP'])}, "
+                f"PW: {len(records_by_type['PW'])}, PT: {len(records_by_type['PT'])}"
+            )
             
             # Group records by date for each work type
             daily_records_by_type = {wt: {} for wt in ['regular', 'SP', 'PW', 'PT']}
@@ -559,8 +566,10 @@ class WorkingHoursCalculator:
 
                     # Move orphaned early check-outs from Day N+1 → Day N
                     for co in orphaned_early_outs[:len(unmatched_late_ins)]:
-                        print(f"🌙 Overnight shift detected for {work_type} on {date_key}: "
-                              f"moving check-out {co.check_in_time} from {next_date_key} → {date_key}")
+                        _calc_logger.info(
+                            f"Overnight shift detected for work_type={work_type} on {date_key}: "
+                            f"moving check-out {co.check_in_time} from {next_date_key} -> {date_key}"
+                        )
                         daily_records_by_type[work_type][date_key].append(co)
                         daily_records_by_type[work_type][next_date_key].remove(co)
 
@@ -697,7 +706,11 @@ class WorkingHoursCalculator:
             grand_pw_hours       = round_base100_hours(sum(week['pw_hours']       for week in weekly_hours))
             grand_pt_hours       = round_base100_hours(sum(week.get('pt_hours', 0) for week in weekly_hours))
             
-            print(f"✅ Employee {employee_id}: Total: {grand_total_hours:.2f}h (Regular: {grand_regular_hours:.2f}h, OT: {grand_overtime_hours:.2f}h, SP: {grand_sp_hours:.2f}h, PW: {grand_pw_hours:.2f}h, PT: {grand_pt_hours:.2f}h)")
+            _calc_logger.info(
+                f"Employee {employee_id}: Total={grand_total_hours:.2f}h "
+                f"(Regular={grand_regular_hours:.2f}h, OT={grand_overtime_hours:.2f}h, "
+                f"SP={grand_sp_hours:.2f}h, PW={grand_pw_hours:.2f}h, PT={grand_pt_hours:.2f}h)"
+            )
             
             return {
                 'employee_id': employee_id,
@@ -723,9 +736,7 @@ class WorkingHoursCalculator:
             }
             
         except Exception as e:
-            print(f"❌ Error calculating working hours for employee {employee_id}: {e}")
-            import traceback
-            print(f"❌ Traceback: {traceback.format_exc()}")
+            _calc_logger.error(f"Error calculating working hours for employee {employee_id}: {e}", exc_info=True)
             raise e
     
     def calculate_all_employees_hours(self, start_date: datetime, end_date: datetime, 
@@ -745,7 +756,7 @@ class WorkingHoursCalculator:
             Dictionary containing hours data for all employees with SP/PW/PT breakdown
         """
         try:
-            print(f"🚀 Starting calculation for all employees with SP/PW/PT consolidation")
+            _calc_logger.info("Starting hours calculation for all employees with SP/PW/PT consolidation")
             
             # Get unique BASE employee IDs (consolidate SP/PW/PT variants)
             base_employee_ids = set()
@@ -762,20 +773,20 @@ class WorkingHoursCalculator:
                             base_employee_ids.add(base_id)
                             
                 except Exception as e:
-                    print(f"⚠️ Error processing employee ID: {e}")
+                    _calc_logger.warning(f"Error processing employee ID during consolidation: {e}")
                     continue
             
-            print(f"👥 Found {len(base_employee_ids)} unique base employees (after consolidation)")
+            _calc_logger.info(f"Found {len(base_employee_ids)} unique base employees (after SP/PW/PT consolidation)")
             
             results = {}
             for base_emp_id in sorted(base_employee_ids):
                 try:
-                    print(f"\n🔄 Processing base employee {base_emp_id}")
+                    _calc_logger.debug(f"Processing base employee {base_emp_id}")
                     results[base_emp_id] = self.calculate_employee_hours(
                         base_emp_id, start_date, end_date, attendance_records
                     )
                 except Exception as e:
-                    print(f"❌ Error processing employee {base_emp_id}: {e}")
+                    _calc_logger.error(f"Error processing employee {base_emp_id}: {e}", exc_info=True)
                     # Return empty result for this employee
                     results[base_emp_id] = {
                         'employee_id': base_emp_id,
@@ -810,7 +821,5 @@ class WorkingHoursCalculator:
             }
             
         except Exception as e:
-            print(f"❌ Error calculating hours for all employees: {e}")
-            import traceback
-            print(f"❌ Traceback: {traceback.format_exc()}")
+            _calc_logger.error(f"Error calculating hours for all employees: {e}", exc_info=True)
             raise e
\ No newline at end of file