Question

in heating ventilation and air conditioning (HVAC) explain what operation is carried out to achieve comfort during summer and in winter

Answer 1

In HVAC the major operations are carried out to achieve comfort during summer and winter are :-

• Controlling temperature
• Percentage of fresh air circulation
• Air Filtration
• Controlling relative humidity

Human comfort conditions are :-

(20- 21 )⁰C effective temperature, (24-26)⁰C Normal temperature and (50-60)% relative humidity. Its valve changes from place to place and working environment.

Controlling temperature (by heating/cooling coil) - In winter it increases its conditioned space temperature and in summer decreases its temperature which is sensed with the help of thermostat installed in conditioned space. conditioned space temperature also depend on working environment.

Percentage of fresh air circulation ( By air handler) - Approx 10 to 20 % fresh air is added during operation and rest room air is added. but its percentage depend on working environment, in case of intensive care unit 100% fresh air circulation take place. In this level of oxygen and carbon di oxide are maintained.

Air Filtration (done by air filters) - Air from conditioned space get filtered to eliminate dust,  bacteria, harmful substance, etc. in this operation pure air deliver to working environment.

Controlling relative humidity (Moisture controller) - If relative humidity is not under comfort zone then human will face discomfort which will lead to excessive sweating drying of skin, etc.