If static pressure in a duct is 1.10" w.c. and velocity pressure is 0.11" w.c., what is the total pressure?

Total pressure in a duct system is calculated by the formula:

Total Pressure = Static Pressure + Velocity Pressure.

In this scenario, the static pressure is given as 1.10" w.c. and the velocity pressure is 0.11" w.c.

When you add these two values together:

1.10" w.c. (static pressure) + 0.11" w.c. (velocity pressure) = 1.21" w.c.

This means the total pressure in the duct is 1.21" w.c., which corresponds to the correct answer. Understanding this calculation is crucial in HVAC systems since total pressure affects airflow and system efficiency. Properly balancing and measuring pressure are key components in ensuring effective system performance.