Question

How to start the operation of HVAC sizing of a building?

Answer 1

• Every HVAC system has basic components in common, although there’s many ways to implement and optimize them.
• Our air conditioner must be precisely sized in order to reach its optimal energy efficiency and performance level. An undersized system won't cool sufficiently and will work overtime in attempt to compensate, causing early wear. An oversized system will cycle on and off frequently, causing temperature swings and hot and cold spots, leaving behind excess humidity, and wasting energy.
• Right sizing” an HVAC system improves efficiency, reduces noise, offers greater cooling/heating comfort and saves money. An oversized system increases installation costs, wastes energy, and costs more in overall operating costs than correctly sized systems
• Most HVAC systems are sized to meet heating and cooling loads occurring around 1% to 2.5% of the time, but an efficient system works most effectively for the conditions occurring 97.5% to 99% of the time, according to the National Institute of Building Sciences.

HVAC system function in large building

• The compressor compresses refrigerant, increasing its pressure and temperature.
• Hot, outside air is blown over the refrigerant vapor by the condenser to liquefy it.
• The expansion valve changes refrigerant into a low-pressure liquid, thus cooling it.
• Heat is transferred by the evaporator to transform the cool liquid to a warmer gas.

No matter how big your building, basic concepts remain the same, though the using of cooling towers and “free cooling” can make things more complex. In an electrical system, the heating cycle is very similar to the cooling cycle.