Our furnace which also heats our water was leaking out a tube on the side of the furance.
The oil company turned off a valve and told us we had a pin hole leak in our water coil if the pressure got to 30 or above. Does this sound correct to you??

Any leak is going to leak more as the pressure goes up. If the pressure outside a coil is 30 pi, then nothing will leak out until the pressure is above 30.