Woocommerce mail after order is completed

Hello,
i have a wordpress site and woocommerce is enabled in it.Ihave different product on my site , when user purchase a product it send mail to user and the mail contains all the information about the order.
I want when the product total cost is less than 100 ,it does not send email.

$order = new WC_Order( $order_id );
$total= $order->get_total();
if($total<100)
{
does not send email
}