replace "Home" link in primary nav with an icon

gistfile1.php

// replace "Home" link in primary nav with an icon
add_filter( 'walker_nav_menu_start_el', 'pp_walker_nav_menu_start_el', 11, 4 );
function pp_walker_nav_menu_start_el( $item_output, $item, $depth, $args ) {
  if (($args->theme_location == 'primary_navigation') && ($item->title == 'Home')) {
    $domDocument = new DOMDocument();
    $domDocument->loadHTML($item_output);
    $domElement = $domDocument->createElement('i', '');
    $domElement->setAttribute('class', 'icon-home icon-large');
    
    $item = $domDocument->getElementsByTagName('a')->item(0);
    $item->nodeValue = '';
    $item->appendChild($domElement);
    
    $item_output = $domDocument->saveHTML(); // <a href="/"><i class="icon-home icon-large"></i></a>
  }
  
  return $item_output;
}