Operating Sequence - Bradford White Brute BNTH Installation And Operation Instructions Manual

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Select one of the controllers listed on the right side
of the screen. Press one of the buttons below the
right column to see the snapshot. See Menu 18.
Menu 18. Typical Control Snapshot
The Show Status button captures the current status
of the I/O of the control only. Show Confi guration
captures the current parameter settings and the
control setup. You can save the snapshot, give it a
name, or send a copy to the USB port.

11.8 Operating Sequence

When there is a call for heat, the unit will close
pump contacts to energize the customer supplied
relay/contactor to start water fl ow. Once the LCI
circuit (fl ow switch, gas pressure switches, LWCO,
and High Limit aquastats) are completed the unit
will start the blower and begin the ignition sequence.
NeoTherm is equipped with a low and high fi re air Brute
pressure switch. The unit will pre-purge at 65% fan
for 30 seconds and prove fan through the blocked
intake switch. Once fan is proven, the blower will
proceed to 24% and the 10 second Pre-ignition timer
will start to allow the HSI to heat up. Once the
Pre-ignition timer has expired the control will open
the Pilot solenoid and the Pilot Flame Establishing
Period (PFEP) will start for 10 seconds to establish
fl ame. Once fl ame has been established and the 10
second timer has expired the control will open the
main valve and the Main Flame Establishing Period
will begin for a period of 5 seconds. If fl ame is
established within those 5 seconds then unit will
proceed to Run, if fl ame does not establish the unit
will post-purge to 100% for 30 seconds and the
sequence for ignition will begin again. For Non
CSD-1 units retry for ignition is 3 times before
Lockout 109 (Ignition Failure) occurs. For CSD-
1 units there is a single retry before Lockout 109
occurs.
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