CleaverBrooks CFC-1000 User Manual

CB FALCON
33 750-265
DHW Loop Demand and Rate
(Hydronic only)
The Domestic Hot Water (DHW) Demand and Rate source
compares a sensor to a setpoint.
A Burner demand will exist if the sensor temperature falls
below the setpoint minus a hysteresis value. Once the burner
demand signal is on, it remains on until the sensor temperature
is above the setpoint plus a hysteresis value, or until the other
selected demand source input (i.e. Remote Stat or DHW
Switch), if any, turns off.
Pump demand may be driven by the a remote stat, or by the
sensor alone.
A Proportional-Integral-Differential controller operates to
generate the source's requested modulation rate.
The DHW function is implemented as shown in Fig. 14.
Fig. 14. Domestic hot water function.
The DHW loop’s ability to override the normal demand priority
is described in the System Operation Settings section.
Otherwise the behavior of each parameter and feature is given
below.
SENSOR
DHW STORAGE
PARAMETER
TERMINALS
INPUT OUTPUT
“pRATE” =
0 TO 99.99% OF CAPACITY
PASS-THROUGH IF PRIORITY<>
DHW STORAGE
DOMESTIC HOT WATER
(DHW )
DHW HIGH
LIMIT ACTIVE
(SUSPEND DHW DURING
DHW HIGH LIMIT CONDITION)
TO/FROM
DHW STORAGE
DHW
MODULATION
SENSOR
T
TOD
DATA SERVER “DSD DHW TEMP”
T=x P=1
T=0 P=0
T=1 P=0
TP
PREHEAT
ACTIVE
TOD
SETPOINT
SETPOINT
PLATE PREHEAT
SETPOINT
ON HYST.
PREHEAT
IF PREHEAT IS ACTIVE,
USE PREHEAT HYSTERESEIS
PREHEAT
ACTIVE
PREHEAT
ACTIVE
DHW FIRING RATE
(USE MIN MODERATION AND ALSO
RESTART THE PID INTEGRATOR AT
THE END OF PREHEATING)
OFF HYST.
ON HYST.
NORMAL
OFF HYST.
P-GAIN
I-GAIN
D-GAIN
PID
DHW BURNER
DEMAND
DHW HEAT
DEMAND
DHW DEMAND SWITCH
DATA SERVER DHW OUTPUT ENABLE
DATA SERVER “DSS DHW DEMAND”
DATA SERVER “DSS DHW TEMPERATURE”
SAVE DHW TEMP AND DHW
DEMAND IF THIS IS ENABLED AND
THEY ARE NOT ALREADY COMING
FROM THE DATA SERVER
DATA SERVER “DSD DHW DEMAND”
TIME SINCE:
BURNER TURN-ON
BURNER TURN-OFF
BURNER
STATE: ON/OFF
HYSTERESIS
STAT
J7-3 120 VAC
EnviraCOM REMOTE STAT
NO DATA
TIMEOUT:
REVERT
TO OFF
SENSOR IS SHORTED
STAT2
SETPOINT DEMAND
SENSOR ONLY
OUTLET (S3S4)
DHW (S6 ONLY)
DHW (S6S7)
INLET (S1)
S6 (DHW TOP)
DHW ENABLE
DHW PLATE DEMAND
T
FUTURE
FUTURE
FUTURE
FUTURE
RESTART (RESTART
INTEGRATOR WHENEVER
A LIMIT OR OVERRIDE
ENDS, OR TURN-ON
OCCURS.)
0%
EnviraCOM TOD
TOD
T

CleaverBrooks CFC-1000 Specifications

General

Brand	CleaverBrooks
Model	CFC-1000
Category	Boiler
Language	English