Senior HVAC Design Engineer Interview Questions and Answers

Yes, water flows inside the pipe for the required tonnage of AC.

• Water flows inside the pipe to carry the heat away from the indoor unit to the outdoor unit.

• The amount of water flow required depends on the tonnage of the AC and the design of the system.

• The water flow rate is typically measured in gallons per minute (GPM) or liters per minute (LPM).

The air velocity at cooling coil depends on the design and specifications of the HVAC system.

• Air velocity at cooling coil is typically between 300-500 feet per minute.

• The velocity can be adjusted based on the cooling load and desired temperature.

• Higher air velocity can improve heat transfer but may also increase noise levels.

• The velocity should be measured and adjusted during commissioning to ensure optimal performance.

ACH (Air Changes per Hour) is used in various fields to measure the amount of air exchanged in a space per hour.

• ACH is commonly used in HVAC design to determine the appropriate ventilation rate for a space.

• In hospitals, ACH is used to control the spread of airborne infections.

• ASHRAE recommends a minimum of 6 ACH for operating rooms and 12 ACH for isolation rooms.

• In cleanrooms, ACH is used to maintain a controlled environment with low levels of particulate matter.

• ACH can also ...read more