This document discusses heating, ventilation, and air conditioning (HVAC) systems. It describes the basic components and functions of HVAC, including temperature control, moisture control, air movement, and air quality maintenance. It also discusses different types of HVAC systems, factors to consider when selecting a system, and provides a case study of the HVAC system used in a hospital in Gulbarga, India. The hospital uses a chilled water system with water-cooled chillers to cool water that is circulated throughout the building to air handlers.

1. •WHAT IS HVAC
H- HEATING
V- VENTILATION
AC- AIR CONDITIONIN
•FUNCTIONS OF HVAC
CONTROL OF AIR TEMPERATURE.
CONTROL OF MOISTURE CONTENT IN THE AIR.
PROPER AIR MOVEMENT.
TO HOLD THE AIR CONTAMINATION WITHIN ACCEPTABLE LIMITS
BASIC COMPONENTS OF AIR CONDITIONING
COMPRESSOR
CONDENSER
THROTTLING DEVICE
EVAPORATOR
INTRODUCTION:

3. VARIOUS AC SYSTEMS

4. •STEPS INVOLVED INDECIDING THE SYSTEM
CALCULATION OF COOLING LOAD REQUIREMENT
SELECTION OF TECHNO-ECONOMICAL SYSTEM
SELECTION OF EQUIPMENT
DESIGNING AIR DISTRIBUTION SYSTEM
DESIGNING WATER DISTRIBUTION SYSTEM
EVALUATION OF SYSTEM TO BE USED
IMPORTANT FACTORS FOR CALCULATION OF COOLING LOAD REQUIREMENT
 USE OF SPACE
 PHYSICAL DIMENSION OF SPACE
 CEILING HEIGHT
CONSTRUCTION MATERIAL
NSIDE ROOM DESIGN CONDITIONS
AMBIENT CONDITIONS
GLASS AREA EXPOSED TO SUN
OCCUPANCY
LIGHTING LOAD
EQUIPMENT LOAD
FRESH AIR REQUIREMENT
INFILTRATION OF OUTSIDE AIR
FACTORS AFFECTING THE SYSTEM SELECTION
BUDGET OF CLIENT
NEED OF CLIENT

5. USE OF SPACE
 AESTHETICS
 FLOOR LAYOUT
DEPTH OF BEAM
LOCATION OF COLUMNS
POWER AVAILABILITY
WATER AVAILABILITY
SPACE FOR SERVICING
TYPES OF CHILLERS
 AIR COOLED TYPE
WATER COOLED TYPE
TYPES OF COMPRESSORS
 RECIPROCATING TYPE
ROTARY TYPE
SCROLL TYPE
 SCREW TYPE
 CENTRIFUGAL TYPE

6. CASE STUDY:
LOCATION:ESIC HOSPITAL GULBARGA
Fully hospital is designed in hvac system/central AC system.
In central AC system there are two types namely: 1.DX SYSTEM
2.CHILLING WATER SYSTEM
Further in chilling water system there are two tyrpes namely: 1.water cool system
2.air cool system
In this hospital chilling system is used of water cool system
Chillers is used for cooling the water
R1F3 liquid/tetra flro is used to clean the water
12 no.of chillers are present in the hospital but present only 5 chiilers are used
One chiller has a capacity of 450 ltr
These chillers are checked once in a day
Source of water:
for this water supplyed directly from BHIMA RIVER
Per day 2-3 lakhs liters of water are used
Thi are ECO-FRIENDLY
This chiilers need 1000kw of energy

7.  WATER CHILLERS ARE COMMONLY CALLED CHILLED WATER SYSTEMS.
AS ITS NAME SUGGEST, THIS SYSTEM MAKES USE OF WATER AS ITS SECONDARY REFRIGERANT.
CHILLER IS USED TO REMOVE HEAT FROM THE WATER WHICH IS THEN CIRCULATED THROUGH OTHER
COMPONENTS TO ABSORB HEAT FROM THE SPACE.
 CHILLED WATER AIR CONDITIONING SYSTEMS ARE COMMONLY USED IN APPLICATIONS THAT NEED
LARGE COOLING CAPACITY SUCH AS HYPERMARKET, INDUSTRIAL PROCESS, COMMERCIAL AIR
CONDITIONING SUCH AS OFFICES AND FACTORIES. MORE AND MORE HOMES ARE USING THIS SYSTEM
TO AIR CONDITIONED THEIR ENTIRE HOUSE BECAUSE OF ITS COST-EFFECTIVENESS AND NO HAZARD OF
HAVING REFRIGERANT PIPED ALL OVER THE HOUSE.
PURPOSE OF CHILLAR:
THE PURPOSE OF A CHILLED WATER SYSTEM IS TO PROVIDE COLD WATER TO AIR-HANDLER
EQUIPMENT FOR THE PURPOSE OF COOLING SUPPLY AIR TO CONTROL SPACE TEMPERATURE.
 WATER IS COOLED TO A PREDETERMINED SET- POINT THAT IS SET WITHIN THE CHILLER ITSELF.
IN A CHILLED-WATER SYSTEM, THE ENTIRE AIR CONDITIONER IS INSTALLED ON THE ROOF OR BEHIND
THE BUILDING.
 A WATER CHILLER COOLS WATER TO BETWEEN 40 AND 45 DEGREES FAHRENHEIT (4.4 AND 7.2
DEGREES CELSIUS).
THE CHILLED WATER IS THEN PIPED THROUGHOUT THE BUILDING AND CONNECTED TO AIR
HANDLERS.
 THIS CAN BE A VERSATILE SYSTEM WHERE THE WATER PIPES WORK LIKE THE EVAPORATOR COILS IN
A STANDARD AIR CONDITIONER.
IF IT'S WELL-INSULATED, THERE'S NO PRACTICAL DISTANCE LIMITATION TO THE LENGTH OF A
CHILLED-WATER PIPE.

8. There are two loops in chillers namely:1.primary loop
2.secondary loop
1.PRIMARY LOOP:
The primary loop utilizes constant volume pumps to maintain constant flow
through the chillers.
This motor are of 20HP
2.SECONDARY LOOP:
The secondary loop utilizes variable volume pumps to pull the chilled water
from the primary loop and distribute it to the system.
 This motor are of 30HP
A primary-secondary system consists of two hydronic loops connected by a de-coupler

9. THE EVAPORATOR COOLS WATER TO ABOUT 45 .
THAT CHILLED WATER IS PUMPED TO COOLING COILS IN THE AREAS BEING COOLED, AND A FAN
DRAWS THE AIR IN THOSE AREAS THROUGH THE CHILLED WATER COILS, COOLING THE AIR.
IN COMPARISON, WITH STANDARD AIR CONDITIONING, THE EVAPORATOR COIL DIRECTLY COOLS
THE AIR. THE REFRIGERANT FLOWS ALL THE WAY TO THE AIR HANDLERS IN THE AREAS BEING
COOLED, AND A FAN DRAWS THE AIR IN THOSE AREAS THROUGH THE EVAPORATOR COILS, COOLING
THE AIR.
 WITH CHILLED WATER AIR CONDITIONING, THE COMPRESSOR IS USUALLY MOUNTED ON A RACK
OR FRAME, WITHIN A FEW FEET OF THE EVAPORATOR THAT COOLS THE CHILLED WATER. IF THE
CONDENSER IS WATER COOLED, IT'S USUALLY MOUNTED ON THE SAME RACK. IF THE CONDENSER IS
AIR COOLED, IT WILL BE INSTALLED OUTSIDE THE BUILDING.
COOLING TOWER :COOLING TOWERS ARE HEAT REJECTION DEVICES USED TO TRANSFER PROCESS
WASTE HEAT TO THE ATMOSPHERE.
COOLING TOWERS MAY EITHER USE THE EVAPORATION OF WATER TO REJECT PROCESS HEAT AND
COOL THE WORKING FLUID TO NEAR THE WET-BULB AIR TEMPERATURE OR RELY SOLELY ON AIR TO
COOL THE WORKING FLUID TO NEAR THE DRY-BULB AIR TEMPERATURE.
 COOLS WATER FROM THE CONDENSER BY DISSIPATING IT INTO THE AIR. TOWER BYPASS VALVE :
CONTROLS CONDENSER WATER FLOW EITHER OVER THE COOLING TOWER OR RECIRCULATES IT
THROUGH THE MACHINE.