1. What is a Steam Boiler Size Calculator?

Definition: This calculator estimates the required boiler size in BTU/h based on steam load, enthalpy of vaporization, and boiler efficiency.

Purpose: It helps engineers and technicians properly size steam boilers for industrial, commercial, or residential applications.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \text{Size} \) — Boiler capacity (BTU/h)
• \( \text{Steam Load} \) — Required steam flow rate (lb/h)
• \( h_{fg} \) — Enthalpy of vaporization (BTU/lb)
• \( \text{Efficiency} \) — Boiler efficiency (0-1)

Explanation: The steam load multiplied by the energy required to vaporize water gives the raw energy needed, which is then adjusted for boiler efficiency.

3. Importance of Proper Boiler Sizing

Details: Correct boiler sizing ensures efficient operation, prevents energy waste, and maintains system reliability while meeting steam demand.

4. Using the Calculator

Tips: Enter the steam load in lb/h, enthalpy of vaporization (default 970 BTU/lb for water at 1 atm), and boiler efficiency (default 0.8 or 80%). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical h_fg value?
A: For water at atmospheric pressure, it's approximately 970 BTU/lb. This varies with pressure and temperature.

Q2: What's a typical boiler efficiency?
A: Modern boilers typically range from 80-95% efficiency, while older models may be 70-80% efficient.

Q3: How do I determine my steam load?
A: Calculate based on process requirements or sum all steam-using equipment demands plus distribution losses.

Q4: Should I add a safety factor?
A: Yes, most engineers add 10-20% to the calculated size for operational flexibility and future expansion.

Q5: Does this work for high-pressure boilers?
A: Yes, but you must use the correct h_fg value for your operating pressure and temperature.