Human Comfort Zone

HVAC

H    -> Heating --- Designing the system for Cold Climate

Heating is the process of increasing the temperature of the substance. In HVAC , heating means designing the system for cold climate according to ASHRAE standards. ( 76^o F / 24^o C human comfort )

According to Thermodynamic 1^st law : Heat is a form of energy which transfer from higher body to lower body temperature

V    -> Ventilation -- Extraction of Air (Exhaust   +   Fresh Air)

It is the process of changing or replacing air in any space to provide high indoor air quality.( ie. To control temperature , replanish oxygen , reverse O₂ , reverse moisture , smoke , heat , air bone bacteria & CO₂ ).Ventilation includes exchange of air to outside as well as circulation of air in the building.

Ac   -> Air Conditioning --- Designing the system for Hot or Dry Climate

Air conditioning is the process of altering the properties of air to more favorable condition.  (primerly temp & humidity) , purifying the air through filter , noise level & by providing fresh air to improve indoor air quality. In HVAC , Designing the system for hot dry or Humid climate.

Human Comfort Zone

Temperature   = 76 ^o  F or 24° C

Humidity        = 50 %

Relative Humidity =     Actual moisture present / Max. Moisture air can hold

Temperature Maximum 78oF ( Summer ) & Minimum 68oF ( Winter ) Relative Humidity = 30 % to 60%

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