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BRADFORD WHITE CORP.

 

 

 

 

Programming. Mode 2 is used in primary-secondary piping hydronic systems without outdoor reset. Mode 5 adds outdoor reset.

Step 1: Install the additional sensor in the primary loop (see Figure 4), and wired to the “SC2” and “SUPS” terminals on the field wiring panel (Figure 23).

Step 2: Remove the factory-installed jumper between the “HtD” and “ComD” terminals on the field wiring panel (Figure 14), and connect a zone valve or pump end switch or other contact closure device (aquastat, etc.) to these terminals to provide an indication of heat demand in the system.

Note: The boiler must have an indication of heat demand to fire. If a zone valve or pump end switch is not connected to the “HtD” and “ComD” terminals, the jumper must be left in place. However, the boiler pump (if equipped) and any pump connected to a contactor wired to the PMP-PMP terminals on the field wiring panel will run continuously and not cycle off according to the setting for the Pump Delay. In addition, the LCD screen will always show “dem” (demand) and will not allow cycling of the display to verify all the sensor settings.

Step 3: Press the three programming buttons to enter ADJUST mode (Figure 25). Press Item to select the programming item, and the ARROW keys to adjust the setting. See Section 6.3 Programming the Temperature Control if more programming instructions are needed.

Recommended settings for hydronic system with

180°F / 83°C primary loop temperature:

Item

MODE

2

2

BOIL TARGET

180

83

BOIL MASS

1

1

DIFF

20

10

DLY

5:00

5:00

°C

Step 4: See Section 6.4.11 Limit Controls. Set both high limit controls at least 25°F / 14°C higher than the BOIL TARGET to allow for temperature rise across the heat exchanger.

6.3.4 Choosing the Mode for your Application

This section describes various applications and the recommended field wiring and Mode selections.

Mode 1: Boiler operates using its own inlet and outlet sensors only, not relying on a remote thermostat, aquastat, or external sensor.

This setup is most commonly found in domestic hot water applications with a continuous run pump.

This is not recommended for other applications. The Copper Brute II is shipped with a jumper

between the “Com D” and “Ht D” terminals, which must remain in place to allow the unit to fire. The unit will fire whenever the outlet temperature cools below the target temperature.

Important Note: If the Copper Brute II is pump- mounted at the factory, or if a field-supplied pump contractor is connected to the Copper Brute II’s pump contactors

(Pmp Pmp), the user must program the controller’s pump delay (DLY) setting to ON. When ON is selected, pump operation is continuous. The unit’s inlet and outlet sensors must be able to detect the temperature in the storage tank in order to control it. Without the tank water continuously running through the heater, the heater will have no way of knowing what the temperature in the tank is, and will not be able to respond to a change in tank temperature. Short cycling or lack of hot water may result if the pump does not run continuously.

Mechanical aquastat in a domestic hot water storage tank.

Remove the jumper from the “Com D” and “HtD” terminals and connect the aquastat’s leads to these terminals. This connection uses a standard, non- powered mechanical aquastat. When the aquastat calls for heat, the Copper Brute II’s temperature control will respond and start the boiler pump (if equipped) and fire the boiler.

If the Copper Brute II is not a pump mounted model, a 24VAC pump contactor may be connected to the “PMP” terminals to control a field installed pump. (If desired, the pump can run continuously, with the aquastat telling the heater when to fire.)

Program the temperature control to use Mode 1. The AUTO/MAN switch must be in the AUTO position in this mode.

Mode 3: Bradford White R2014800 sensor installed in the domestic hot water storage tank.

The Copper Brute II ships with a jumper between the “Com D” and “Ht D” terminals. Verify this jumper is in place, and connect the sensor leads to the “S C2” and “SUP S” terminals. When the sensor detects a temperature below the target temperature, the control will respond and start the heater pump (if equipped) and fire the heater.

If the heater is not a pump mounted model, a 24VAC pump contactor may be connected to the “PMP” terminals to control a field installed pump. (If desired, the pump can run continuously).

Program the temperature control to use Mode 3. The AUTO/MAN switch must be in the AUTO position in this mode.

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Bradford-White Corp BWCH Choosing the Mode for your Application, Mechanical aquastat in a domestic hot water storage tank