To anyone reading this now, DACrosby’s answer still works except you have to wrap the array keys within the $value[] array with quotes (e.g. ‘field_54aa5beb008b1’ )
add_filter('acf/load_value/key=field_54aa5b3b008b0', 'afc_load_my_repeater_value', 10, 3);
function afc_load_my_repeater_value($value, $post_id, $field) {
if ($post_id === false) {
$value = array();
$value[] = array(
'field_54aa5beb008b1'/* Correct */ => 'Hours',
field_54aa5c25008b2 /* Incorrect */ => 1
);
}
return $value;
}