Conference Pear Tree - no fruit

Although Conference can be self-fertile, another pear tree in the vicinity will ensure a better crop. You could always persuade a neighbour to plant one?
Also, pears are notoriously slow to start cropping - the fruits on it when you bought it may have been because it was surrounded by other trees in the sales area but now it's on its own, it may take longer to settle down to a productive life.

This year take some pollen from another pear tree with a tiny soft paint brush and pollinate yourself one branch just to see if pollen is the problem if this works get another tree. Actually im not sure if this really works but I tried it with my little ballarina apple tree and was amazed with the amount of apples on one small tree wether this was because of my hand pollinating or some other reason im not 100pc sure.