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Bradford White Corp.
12.1.2 flap Valve Status Check
Each boiler includes two burners, and each burner
has a flap valve. See Fig. 123.
If one burner in a boiler is operating, and the other
is not, the flap valve for the burner that is off will
remain closed to prevent air from moving backwards
through the burner that is not operating. Before the
Lead/Lag Master controller will allow the system
to operate, it must be able to determine whether
each of these flap valves is open or closed. If the
controller cannot find a signal from one of the
flap valves, the control system will act to prevent
backflow by energizing the blower of the control
with the bad flap valve. If this cannot be done
the
control will not allow the whole system to run.
If
the flap valve identifications are not set correctly, the
control system will present a “HOLD 119 – Control
Interaction Fault” on the display. For this reason, it
is important that all of the flap valves be identified
correctly.
12.2 about lockouts, Holds, and
alerts
The control system on the Brute Elite responds to
three kinds of trouble indications:
•
A “lockout” is caused by a serious problem
that might involve a safety issue. Once
the controller enters a lockout, the burners
will shut down, and will not be allowed to
run again until the cause of the problem is
corrected, and you reset the control system.
The controller will also trigger a lockout if you
change a safety-related parameter, but do not
finish the “verification” process. (For more
information on verification, see Section 8.8)
Primary
burner
Primary
controller
Flap
valve
Flap
valve
Secondary
controller
Secondary
burner
Operator
interface
Boiler 1
fig. 123 - flap Valve arrangement
During a lockout condition, the image of the
affected controller on the Home screen will
appear in red. A bell symbol will appear in the
upper left-hand corner of the control screen.
The system maintains a “history” of the 15
most recent lockouts.
•
The system may enter a “hold” for a period
of time before locking out. This allows the
controller to see if the error becomes resolved
prior to the hard lockout. Holds can occur
while the boiler is operating.
•
An “alert” indicates that some feature of the
control system’s operation was not correct,
delayed or waiting for a response. This
indicates a change in state of the control
system and doesn’t necessarily mean there
is a problem. For example, Alerts occur as
the fan speed transitions from the pre-purge
RPM to the startup RPM. This indicates that
the control system is waiting for a condition
to be satisfied. No Reset is required to
recover from an alert. The system maintains
a “history” of the 15 most recent alerts.
Sometimes it can be helpful to check this list
as a troubleshooting aid.
12.2.1 responding to a lockout, Hold, or
alert
1. If a problem occurs while the system is
starting up, the system will declare a Hold.
A brief explanation of the cause of the Hold
will appear in an orange bar across the bottom
of the screen. If you tap the orange bar, the
system will present more information about
the Hold.
Summary of Contents for BNTH1000
Page 2: ...Bradford White Corp...
Page 12: ...Page 8 Bradford White Corp Fig 6 Dimensions BNT 1700...
Page 38: ...Page 34 Bradford White Corp Fig 21 Ladder Diagram...
Page 39: ...Page 35 Brute Elite Boilers and Water Heaters Fig 22 Wiring Diagram...
Page 40: ...Page 36 Bradford White Corp...
Page 52: ...Page 48 Bradford White Corp Fig 51 Connection Terminals...
Page 130: ...Page 126 Bradford White Corp Fig 141 Rear Panel BNT1000 Fig 142 Rear Panel BNT1700...
Page 131: ...Page 127 Brute Elite Boilers and Water Heaters Fig 143 Machine Frame BNT1700...
Page 132: ...Page 128 Bradford White Corp Fig 144 Front Panels and Covers BNT1000 and BNT1700...
Page 133: ...Page 129 Brute Elite Boilers and Water Heaters Fig 145 Burners and Combustion Chamber BNT1000...
Page 134: ...Page 130 Bradford White Corp Fig 146 Burners and Combustion Chamber BNT1700...
Page 136: ...Page 132 Bradford White Corp Fig 149 Burner Detail BNT1700...
Page 139: ...Page 135 Brute Elite Boilers and Water Heaters This page intentionally left blank...
Page 140: ...Page 136 Bradford White Corp This page intentionally left blank...