Hi @realph
Perhaps you can simplify your code down to:
<?php if( have_rows('repeater') ): ?>
<?php while( have_rows('repeater') ): the_row();
$min = get_sub_field('min');
$max = get_sub_field('max');
echo 'Min = ' . $min . '(UK) ' . $conversion[ $min ] . '(US)';
echo 'Max = ' . $max . '(UK) ' . $conversion[ $max ] . '(US)';
?>
<?php endwhile; ?>
<?php endif; ?>