Since the pads are what makes a unit cool as water passes through and evaporates they can be a big performance factor.
There are two main types of cooling pads called Fiber and Rigid, each of which can be built with different material.
Types of Fiber Swamp Cooler Pads
Aspen pads use wood shavings which is all natural and makes them low-cost, work great, and when new have a nice clean fresh smell to them.
The only real downside to Aspen pads is they need to be replaced more often than most other types.
If the water has a lot of calcium in it this can make less of a difference as all pads will become clogged quickly and need replacing.
Aspen pads have been used for many years and is a good material to use with a swamp cooler as long as they are regularly replaced during maintenance.
Example eAspen Pads on Amazon
Dial 3005 Mfg. Aspen Cooler Pads
The local water can have an impact how long they last since calcium build up will block any pad which would need to be replaced.
Often synthetic can be cleaned and reused in many situations, plus they resist mold which can be a big plus.
Synthetic works well enough for cooling and are used a lot by landlords since they usually last longer.
Example Synthetic Pads on Amazon
Dial Manufacturing 3072 28″ X 34″ Dura-Cool Pre Cut Pads
They are also very durable and can often be cleaned and reused in some situations.
The type of swamp cooler pad used will have a direct effect on cooling and air quality.
Personally, I prefer the Aspen wood shaving type which works the best in my opinion but does need more maintenance.
Most Aspen pads will need to be replaced every year for the best performance.
There are many who use the synthetic type with good success.
Which type is used very much a personal option with most simply replacing what was in the unit previously.
Do you have a preference? Let us know in the comments below.