
ENGINEERING CMANUAL OF AUTOMATION CONTROL
AIR HANDLING SYSTEM CONTROL APPLICATIONS
248
YEAR-ROUND SYSTEM CONTROL PROCESSES
HEATING, COOLING, AND ECONOMIZER
Functional Description
M10478
OA
EA
RA
SA
3
2
ON
ON
1
100
5
100
16
19
4
20
NORMAL
ECONOMIZER DECISION.
REFER TO PREVIOUS
ECONOMIZER OPTIONS
OA MINIMUM SETPOINT
(NOTE: THE TEST AND BALANCE
INITIAL VALUE FOR PROPER
VENTILATION IS 22)
7
6
22
CONTROL
PROGRAM
22
96
17
14
18
105
55
SUPPLY AIR
TEMPERATURE
SETPOINT
SPACE
HEATING
DEMAND
100
0
75
55
SUPPLY AIR
TEMPERATURE
SETPOINT
CHW
COOLING
DEMAND
0
100
75
57
SUPPLY AIR
TEMPERATURE
SETPOINT
FREE
COOLING
DEMAND
0
100
64
21
0
36
SUPPLY
FAN
PERCENT
OPEN
NC
NO
NC
SPACE TEMPERATURE
15
59
64
11
9
10
74
76
2.0
8
76
SETPOINT
13
72
SETPOINT
100
0
CHILLED WATER COOLING
SETPOINT = FREE COOLING
SETPOINT PLUS
FREE COOLING
SETPOINT
(1.5 MINIMUM)
12
2.0
HEATING SETPOINT = FREE
COOLING SETPOINT MINUS
(1.5 MINIMUM)
Item
No.
Function
1-3
Control system energizes when fan is turned
on (See FAN SYSTEM START-STOP
CONTROL).
4-6
Mixing dampers modulate to maintain
minimum ventilation value and free cooling
SA temperature setpoint.
7
Economizer enables free cooling when OA is
appropriate.
8
Space temperature dictates heat and cool
demands.
9-13
Free cooling setpoint and heat/cool deadband
values determine the SA temperature setpoint
for hot and chilled water control setpoints.
Software has a minimum 1.5 Fahrenheit
degree heating and cooling deadband.
14
Heat demand varies SA temperature setpoint.
15,16
Hot water valve modulates to maintain SA
Summary of Contents for AUTOMATIC CONTROL
Page 4: ...ENGINEERING MANUAL OF AUTOMATIC CONTROL iv ...
Page 6: ...ENGINEERING MANUAL OF AUTOMATIC CONTROL vi ...
Page 11: ...ENGINEERING MANUAL OF AUTOMATIC CONTROL CONTROL FUNDAMENTALS 1 CONTROL SYSTEMS FUNDMENTALS ...
Page 12: ......
Page 46: ...ENGINEERING MANUAL OF AUTOMATIC CONTROL CONTROL FUNDAMENTALS 36 ...
Page 66: ...PSYCHROMETRIC CHART FUNDAMENTALS 56 ENGINEERING MANUAL OF AUTOMATIC CONTROL ...
Page 128: ...ENGINEERING MANUAL OF AUTOMATION CONTROL ELECTRIC CONTROL FUNDAMENTALS 118 ...
Page 158: ...MICROPROCESSOR BASED DDC FUNDAMENTALS 148 ENGINEERING MANUAL OF AUTOMATIC CONTROL ...
Page 210: ...ENGINEERING MANUAL OF AUTOMATIC CONTROL BUILDING MANAGEMENT SYSTEM FUNDAMENTALS 200 ...
Page 440: ...ENGINEERING MANULA OF AUTOMATIC CONTROL INDIVIDUAL ROOM CONTROL APPLICATIONS 430 ...
Page 516: ...ENGINEERING MANUAL OF AUTOMATIC CONTROL GENERAL ENGINEERING DATA 506 Notes ...
Page 517: ...ENGINEERING MANUAL OF AUTOMATIC CONTROL GENERAL ENGINEERING DATA 507 Notes ...
Page 518: ...ENGINEERING MANUAL OF AUTOMATIC CONTROL GENERAL ENGINEERING DATA 508 ...