Blower Orientation

Blowers come in 4 handings and 2 orientations.
Some manufacturers also build machines so that airflow must pass through from one port (inlet) to another (discharge) in a particular direction, amounting to 8 possible variations.

Describing them carefully is key to ensuring you receive the blower you require.
This is particularly important where direction is requested by the manufacturer: the machine will not work properly and you may void the warranty if the blower is not run in the direction it was designed to.

First we will look at the visual cues and some of the ways that different manufacturers describe them which can been seen below.

You will need to be looking at the blower from the driving side of the machine so you can see the input drive shaft.

Directional rotation may need to be identified for some blowers; it's best to have this information on hand.
Rotational direction is usually identified as clockwise or counter-clockwise: and is referring to the direction which the drive shaft is rotating when looking directly at it.
Always make sure you're refering to the blower direction, this is particularly important on direct coupled machines.

Some machines will have a small directional arrow plate fixed to the casing near the drive shaft location.

If you are unable to identify the direction of rotation, you can try to identify which side of the blower is the inlet side.
This is demonstrated in the illustrations below.