Exam Question

### (a) State why the presence of oil in boiler water is considered serious.
The presence of oil in boiler water is considered extremely serious due to its detrimental effects on boiler efficiency, safety, and longevity. The primary reasons are:
* **Reduced Heat Transfer Efficiency and Localized Overheating:**
* Oil has a significantly lower thermal conductivity compared to water. When even a thin film of oil adheres to the heat transfer surfaces (boiler tubes or plates), it acts as an insulating layer.