Question 1

How do I convert PSI to kPa?

Accepted Answer

To convert PSI (pounds per square inch) to kilopascals (kPa), multiply by 6.89476. For example, 100 PSI = 100 × 6.89476 = 689.5 kPa. Conversely, to convert kPa to PSI, divide by 6.89476 (or multiply by 0.14504). Standard atmospheric pressure is 14.696 PSI = 101.325 kPa.

Question 2

How do I convert CFM to m³/h?

Accepted Answer

To convert cubic feet per minute (CFM) to cubic meters per hour (m³/h), multiply by 1.6990. For example, 1,000 CFM = 1,699 m³/h. To go the other way, multiply m³/h by 0.5886 to get CFM. HVAC airflow is typically expressed in CFM in North America and m³/h or L/s in metric countries.

Question 3

How do I convert GPM to L/s?

Accepted Answer

To convert US gallons per minute (GPM) to liters per second (L/s), multiply by 0.06309. For example, 100 GPM = 6.309 L/s. To convert L/s to GPM, multiply by 15.850. Plumbing and fire protection flow rates in North America are expressed in GPM; metric engineering typically uses L/s or m³/h.

Question 4

How do I convert HP to kW?

Accepted Answer

To convert mechanical horsepower (hp) to kilowatts (kW), multiply by 0.7457. For example, 100 hp = 74.57 kW. To convert kW to hp, multiply by 1.3410. Note: there are several definitions of horsepower — mechanical (550 ft·lbf/s), electrical (746 W), and metric (PS = 735.5 W). The mechanical horsepower (745.7 W) is standard in NEC motor tables.

Question 5

How do I convert Fahrenheit to Celsius?

Accepted Answer

To convert Fahrenheit (°F) to Celsius (°C), use the formula: °C = (°F − 32) × 5/9. For example, 32°F = 0°C, 212°F = 100°C, 98.6°F = 37°C. To convert Celsius to Fahrenheit: °F = (°C × 9/5) + 32. Note that −40°C = −40°F is the point where the two scales intersect.