Internet Version for Reference Only
Copper Brute II | Page 27 |
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6.3.4 Boiler Maximum (BOIL MAX)
The boiler maximum (BOIL MAX) is the highest water temperature that the control is allowed to use as a target temperature. If the control does target BOIL MAX, and the heater outlet sensor is near the BOIL MAX temperature, the MAX segment turns
on in the LCD while the target, inlet, outlet or supply temperature is viewed (see Figure 14).
Figure 14. Temperature Control Min & Max Graph.
6.3.5Boiler Target Temperature
The target temperature is determined from
the mode of operation. The control displays the temperature that is currently trying to maintain at the operating sensor as BOIL TARGET in the View menu. The operating sensor for modes 1, 3 and 4 is the outlet sensor (on the heater). The operating sensor for modes 2 and 5 is the supply sensor (in the system or primary loop). If the control does not presently have a requirement for heat, it displays “- -
6.3.6 Pump Operation
The pump terminals (Pmp Pmp) are energized with 24 VAC to control a field supplied pump contactor. During set point operation (modes 1 and 2), the terminals are energized whenever there is a heat demand. During dedicated DHW operation (mode 3), the terminals are energized whenever there is an internal heat demand. During outdoor reset (modes 4 and 5), the terminals are energized whenever there is either a heat demand and the control is not in Warm Weather Shut Down (WWSD), or whenever there is
a set point demand. During WWSD, if the pump has not operated at least once every 70 hours, the control energizes the terminals for 10 seconds. This minimizes the possibility of the pump seizing during a long period of inactivity. During External Heater Operation (mode 6), the pump contact closes whenever there is a heat demand.
Boiler Purge (PUMP DLY) – After a demand is satisfied, the control continues to operate the pump for a period of time. The length of time that the pump continues to run is based on the pump delay setting.
Once the last stage of the control turns off, the control keeps the pump contacts energized for the time selected (between 0 and 10 minutes). When OFF is selected, there is no purging. When ON is selected, pump operation is continuous. Also, during outdoor reset, with the pump delay set to ON, the pump continues to run even during Warm Weather Shut Down.
6.3.7 Set point Operation
When either mode 1 or 2 is selected, the control controls the water temperature based on a fixed set point. The set point temperature is set using the BOIL TARGET item in the Adjust menu.
Heat Demand – For “heat demand” to exist, there must be continuity between the Com D (common demand) and the Ht D (heat demand) terminals. The heater ships with a jumper between these terminals.
The control also evaluates the sensor(s) installed in the system, including the outlet sensor provided on the heater when using mode 1. When the control senses continuity between Com D and Ht D terminals, and that the sensor reading is below the target temperature, the control will activate the Dem segment in the display.
The control energizes the pump (on pump mounted heater) and energizes the Pmp Pmp terminals. The heater pump segment is turned on in the display. The control then operates the stages to maintain the set point temperature.
6.3.8Dedicated Domestic Hot Water
When mode 3 is selected, the control provides
dedicated domestic hot water operation.
Internal DHW Demand – A sensor is required to be connected on the SC2 and Sup/S terminals. An internal demand for DHW is generated when the temperature demand for DHW sensor drops 1⁄2 of the tank differential setting below the desired DHW tank temperature. The TANK TARGET setting is used to set the desired DHW tank temperature.
Once an internal demand is generated, the Dem segment turns on in the LCD. The control then closes the Pmp Pmp contact, which starts the pump and the control turns on the heater pump segment in the display. The control then operates the stages to maintain the programmed heater target temperature at the heater outlet sensor.
