Untitled

<script>
...
jQuery(document).ready(function($) {
        $('#printerButton').click(function(){
            openPrintDialogue();
        });
    });
    function openPrintDialogue(){
        $('<iframe>', {
            id: 'frame',
            scr: 'path/to/my/external/html/file',
            name: 'myiframe',
            class: 'printFrame'
        })
          .appendTo('body');

          window.frames['myiframe'].focus();
          window.frames['myiframe'].print();

          setTimeout(() => { $(".printFrame").remove(); }, 1000);
    };
...
</script>
<html>
...
<input type="button" id="printerButton" name="print" value="Print It" />
...
</html>