#wpadminbar #wp-admin-bar-wp-logo>.ab-item {
background: url(//www.thefriaryguildford.com/images/cg_icon.png);
background-size: 23px 23px;
background-repeat: no-repeat;
background-position: center center;
}
#wpadminbar #wp-admin-bar-wp-logo>.ab-item .ab-icon:before {
display: none;
}