Hot Water with Boiler Pump Modulating Lead/Lag

Chief DispatcherFeatures

[Technical Information]

The Chief Dispatcher Model JC-CDHWBP optimizes hot water system performance and helps extend Cast Iron Sectional, Finned-Tube, Fire Box or Flexible Tube boiler life.  Boiler pump sequencing ensures accurate temperature sensing and boiler cool down.

JC-CDHWBP

2-7 Fully Modulating Boilers

  • Hot water supply header temperature is maintained using accurate PID control
  • “Unison” boiler modulation to ensure even heat delivery
  • Lag boilers are brought up to the “Unison” firing rate using a predetermined Ramp Rate to meet the heating load with minimum overshoot
  • When desired, the operator may set the “Unison” firing rate manually

Boiler Pump Sequencing

  • It keeps the lead boiler pump running to ensure accurate header temperature sensing
  • Provides pump shutdown delay for boiler cool down

Outdoor Reset

  • Saves energy by lowering supply header temperature setpoint as the outside air temp increases
  • Operating cost is reduced during warmer days
  • Hot water supply setpoint may be set manually

Time of Day / Week Setback

  • Saves energy by lowering supply header temperature setpoint during times when heating requirement is reduced, such as at night or on weekends and holidays

Domestic Hot Water Priority

  • A temperature switch will override any setpoint input and force the header supply temperature setpoint to a Domestic Hot Water Setpoint
  • A relay output is available to start a domestic hot water pump if required

Condensing Boiler Logic

  • Maximizes the number of boilers running near low fire to maximize efficiency

5 Boiler Controller Front Panel Shown

Front Panel
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Panel Details

Controller:

Case Size:

Enclosure Type:

PWC (Click here for a complete hardware specifications)

19¼" H X 18" W X 8½" D

Wall mounted, Weight: 55 lbs.

Inputs

Hot Water Header:

Outdoor Air:

BAS Reset Setpoint:

BAS Boiler Disable:

Limits:

Boiler Lockout:

Domestic HW Priority:

0 to 300° F, Thermistor

Thermistor (non “-BAS” version)

4-20 mAdc (“-BAS” version)

120 Vac, optically isolated

120 Vac, optically isolated (each boiler)

120 Vac, optically isolated (each boiler)

120 Vac, optically isolated

Outputs

Modulation:

Boiler Start:

Pump Start:

Domestic HW Circulation Pump:

Isolated 4-20 mAdc or 0-135 ohm (each boiler)

Dry contact, 8FLA, ½ HP, 120 Vac (each boiler)

Dry contact, 8FLA, ½ HP, 120 Vac (each boiler)

Dry contact, 8FLA, ½ HP, 120 Vac

 

Ordering Information

Optional Features Catalog Number
Historical Trending 190604
Telephone Modem 190603
Building Automation System (BAS) add "-BAS" suffix
Condensing Boiler Logic add "-C" suffix
Order Sensors Separately (Quantity as Required) Catalog Number
Hot Water Thermistor Temperature
Sensor 0 to 300F, 4 1/2" depth
70610
Thermowell, SS, 4 1/2" x 1/2" NPT 70610W
Outside Air Thermistor Temperature
Sensor with weatherproof cover
70612