Preferred Instruments • 31-35 South Street • Danbury, CT 06810 • P: (203) 743-6741 F: (203) 798-7313www.preferredinstruments.com

Chief DispatcherModel JC-CDHWF

Condensing Boiler Modulating Control System

OverviewSDI-JC-CDHWF

2-10 Modulating Condenser Boiler Controller:

Hot Water Supply Header Temperature Control • Outdoor Reset Based Setpoint • Time of Day / Day of Week Setback Schedules • Building Automation System (BAS) Setpoint

“Smart” Boiler Sequencing • Building Automation System – Disable Boilers • Boiler Firing Rate based Start-Stop • Header Temperature based Start-Stop • Lead-Lag Sequence

MODULATING LEAD / LAG

The Chief Dispatcher is a standard, application specific Modulating Lead / Lag Controller for Hot Water Boiler Systems.

FEATURES

• Condensing Boiler Logic Maximizes Lower Firing Rate Operation To Increase Efficiency • Hot Water Boiler “Header” or “Boiler” Pump Sequencing Powerful Capabilities Reduce Commissioning Time

• “Smart” Boiler Sequencing Improved Response Time

• Field Configurable Number Of Boilers Remote Setpoint Rotation Schedule Quicker Deliveries and Commissioning

• “Plant Overview”, “Alarm”, “Historical Trend” Displays Enable Informed Initial Setup and Process Assessment

• Direct and Local Engineering Technical Support

• HOA Switches Disable Boilers That Are Off-Line and Control Manually

INTRODUCTION

Chief Dispatcher with key lockable viewing window open

Chief Dispatcher front view with both doors open

SYSTEM OVERVIEWCHIEF DISPATCHER MODEL JC-CDHWF

2-10 HOT WATER BOILERS

SystemReturn

SystemSupply

Boiler Start DO

DI BAS Disable All Boilers

Fuel Input DI

Typical for allBoiler

Typical for allPump

Headered PumpControl Option

AI Outside Air Temp

DI DHW Priority Command

AI Hot Water Supply Header Temp

DI Pump Flow Proven

RO Pump Start

TE

TE

FS FS

Alphanumeric Pager

PWC_Remote

����������

Firing Rate AO

PREFERRED

UTILITIES

or Remote SP from BAS

Typical for All Pumps

Typical for All Boilers

“SMART” BOILER SEQUENCINGBoilers are automatically sequenced on/off to ensure that the number of boilers in service meets hot water demand. If any boiler fails to start when called, or if a boiler trips during operation, the Chief Dispatcher immediately starts another boiler to replace the faulted boiler. The operator may manually select the lead boiler or allow the lead boiler to rotate automatically. Additionally, the total number of boilers in service may be set automatically or manually as selected by the operator or all boilers may be shutdown by a building automation system (BAS) ‘Enable/Disable’ contact input.

EASY INSTALLATION / EASY SETUPThe Chief Dispatcher integrates Modbus communications, relays, 24Vdc power supplies, and outdoor reset functions into a single wall mountable controller. Simple menu style fill in the blanks setup displays minimize commissioning and training time.

LARGE LCD GRAPHIC DISPLAYLCD graphic display brings plant overviews, outdoor reset, alarms and event status and setup displays right to the operator’s touch.

HARD MANUAL BACKUPHard-wired control switches and dials provide simple manual control for easy troubleshooting and service. Each boiler has an individual firing rate bar graph, a manual firing rate output knob, and an Auto/Manual switch.

ALARMS / EVENT SUMMARYUp to 200 alarms, system events and operator actions are listed in “first in first out” order with a time/date stamp. Alarms include system fault, boiler failure and both over and under temperature conditions.

OUTDOOR RESET Energy is saved by lowering the Hot Water Supply (HWS) temperature setpoint as the outside air temperature increases. Operating cost is reduced during warmer days. When desired the operator may set the HWS setpoint manually.

TIME OF DAY / WEEK SETBACK This feature is used in heating applications to save energy by lowering the Hot Water Supply (HWS) temperature setpoint during times when the heating requirement is reduced, such as at night or on weekends and holidays.

BUILDING AUTOMATION SETPOINTA remote hot water supply temperature setpoint can be used intead of the outside air temperature setpoint. This setting is field adjustable.

MODBUS COMMUNICATION INTERFACEA factory-configured RS485 Modbus interface is available for building automation or SCADA system monitoring and control.

OPTIONS

HEADERED PUMP CONTROL (OPTION ‘-H’)Headered circulating pumps are controlled to ensure a continuous flow of water through the heating system. Pumps are controlled for one handling the plant and a tripped pump is automatically replaced with a standby unit. The lead pump can be rotated automatically or manually.

HISTORICAL TRENDS (OPTION P/N 190604)Easy to use four pen charts allow quick hot water system assessment and maintenance monitoring, such as header temperature and boiler operating hour trends.

TELEPHONE MODEM (OPTION P/N 190603)The modem allows the Chief Dispatcher to dial out to an alphanumeric pager and allows a technician to dial in to the Chief Dispatcher to view all Chief Dispatcher displays and make tuning adjustments.

The Chief Dispatcher Model JC-CDHWF will optimize hot water system performance and help extend boiler life.

SYSTEM OVERVIEW

SPECIFICATIONS

Model Name BoilersOutput to

boilersCondensing

LogicHeader Pumps

JC-CDHWF-05-I-C 2-5 4-20mA XJC-CDHWF-10-I-C 6-10 4-20mA X

JC-CDHWF-05-I-C-H 2-5 4-20mA X XJC-CDHWF-10-I-C-H 6-10 4-20mA X X

MODEL NUMBER LIST

MODEL NUMBER DESCRIPTIONJC-CDHWF-10-I-C-H Hot water boiler modulating lead/lag controller

Header Pump option-H = Include two header pump outputs

Condensing boiler modulating control option-C = Condensing boiler modulating control logic is used

Boiler firing rate analog output cards -I = 4-20mA

Number of boilers (5 or 10)

Preferred Instruments • 31-35 South Street • Danbury, CT 06810 • P: (203) 743-6741 F: (203) 798-7313www.preferredinstruments.com