Honeywell AUTOMATIC CONTROL SI Edition, Engineering Manual

Page: 343 / 512

ENGINEERING MANUAL OF AUTOMATIC CONTROL
CHILLER, BOILER, AND DISTRIBUTION SYSTEM CONTROL APPLICATIONS
333
Item No. Function
1 ON-OFF-AUTO function for secondary
pumping system
2 ON-OFF-AUTO function for heating system
3 Selects lead boiler.
4 Heating system start point (Outside air
temperature).
5,6 ON-OFF-AUTO function for primary pumps.
7,8 OFF-AUTO function for boilers.
9 Heating system stop point (Outside air
temperature).
10,11 Operator information.
DUAL BOILER PLANT CONTROL
FUNCTIONAL DESCRIPTION-
Fig. 48. Dual Boiler Plant Control Graphic
12-14 Valve modulates to prevent entering water from
dropping below low limit setpoint (63
°
C).
15-18 Secondary water setpoint reset from OA.
19,20 Valve modulates to prevent entering water from
dropping below low limit setpoint (63
°
C).
21-23 Operator information.
24 Icon, selects the Boiler System Control
dynamic display (Fig. 49).
25,26 Software signal selection functions, allows
valve to control secondary HW temperature,
subject to boiler low limits.
27 OA reset valve control PID.
AUTO
43
82
13
-15
HOT WATER TEMPERATURE
RESET SCHEDULE
OUTSIDE AIR
TEMPERATURE
HOT WATER
TEMPERATURE
SET POINT
SECONDARY
HOT WATER
RETURN
SECONDARY
HOT WATER
SUPPLY
SETPOINT
% SPEED
AUTO
AUTO
82
44
S
AUTO
AUTO
31
00
S
BOILER
SYSTEM
CONTROL
HEATING SYSTEM
ON-OFF-AUTO
SELECTOR LOW LIMIT
SET POINT
BOILER
LEAD SELECTOR
BOILER
SYSTEM
OFF
BOILER
SYSTEM
ON
VALVES DISPLAY
% OPEN TO
SECONDARY
RETURN
OUTSIDE AIR
TEMPERATURE
DECOUPLER
CROSSOVER
OUT
BOILER
BOILER
NO
NC
PID
SP
IN
2
1
26
27
25
12
C
P1
P2
7
5
°
F
PUMP P1
ON-OFF-AUTO
SELECTOR
PUMP P2
ON-OFF-AUTO
SELECTOR
SECONDARY PUMP
SYSTEM
ON-OFF-AUTO
SELECTOR
BOILER -1
OFF-AUTO
SELECTOR
BOILER -2
OFF-AUTO
SELECTOR
PS
4
3
9
2
18
24
21
15
17
1
16
8
19
6
11
23
10
22
13
14
20
57
68
68
OFF
63 71
29.5
AUTO
16
1
18
-1
64
ON
M15266