How does fouling affects the performance of a heat exchanger?

Fouling:

When rust or undesired material deposit in the surface of heat exchanger, is called fouling of heat exchanger.

Effect of heat exchanger are as follows"

1. It decreases the heat transfer.

2. It increases the thermal resistance.

3. It decreases the overall heat transfer coefficient.

4. It leads to increase in pressure drop.

5. It increases the possibility of corrosion.