Direction of Flow

["Ben Prince" <blprince2@comcast.net>]

On the right side of my BN1, there is a valve on the block that connects to a
heater hose.  On the left side near the water pump, a second hose/ pipe runs
to the heater.

What is the direction of coolant flow through the heater?  Which of the two
tubes is the heater inlet?   Does it make any difference which hose connects
to which fitting on the heater?

Thanks,
Ben