Boiler interview questions and answers

Power Plant & Utility Study Guide · Original educational resource · 25 October 2026. Print or save as PDF using your browser. Not an operating procedure or certification.

Why record feedwater temperature?

It changes inlet enthalpy and the heat required per kilogram of steam.

Does a high ash LOI prove low total air?

No. Sampling, fuel properties, mixing and residence time can also contribute.

Why compare fuel on the same moisture basis?

A dry-basis value cannot directly represent delivered wet fuel.

Can higher SFR alone prove improved boiler efficiency?

No. Fuel calorific value and steam/feedwater conditions may have changed.

Does clear water prove suitable boiler feedwater?

No. Dissolved contaminants can be invisible.

Why does wet steam complicate pressure-drop prediction?

Two-phase flow changes momentum, density and drainage behaviour.

What comes first after an abnormal indication?

Apply the approved alarm response and communicate; verify without exposing anyone to danger.

What makes a useful maintenance record?

Symptoms, evidence, work performed, parts, verification and follow-up responsibility.

Why can cost per tonne rise at low load?

Fixed costs are spread over less steam and part-load losses may rise.

How do SFR and specific fuel consumption differ?

SFR is steam mass divided by fuel mass; specific fuel consumption is its reciprocal for the same period.

Engineering references

For contractual tests, agree the applicable current test code, boundary, corrections and uncertainty with the responsible engineer. These tools are not certified acceptance-test software.