Installation / Operation Instruction Manual

Page 31
Brute Deluxe (200, 300, 400), Install & Operating
6.D Sequence of Operation
If a eld-supplied pump is properly wired to the
unit, or if the unit is pump-mounted, the pump will be
energized.
Once the water ow switch makes, if all of the
safety interlocks are closed, the ignition module will
energize the blower(s) for a 15-second pre-purge,
followed by a 40-second period to allow the ignitor to
heat.
The ignition control energizes the blower. The
blower pressurizes the air box (which supplies air to
the burners) and closes the normally-open contact
on the airow pressure switch. The blocked vent
pressure switch senses the pressure in the exhaust
plenum. This switch opens if the pressure is excessive
(as an indicator of a blocked vent). When these two
pressure switches are closed, voltage is sent to the
PSW terminal on the ignition control, which allows the
ignition module to proceed with the ignition sequence.
If the airow proving circuit is not proven,
ignition module will lock out. Section 6.5 describes
the result of air ow faults in more detail.
When the ignition control gets the signal at the
PSW terminal, it will energize its MV terminal, which
sends power to the stage one (or on/o) main valve.
After a 7-second trial for ignition, the ignitor
switches to ame sense mode. If a ame is not
detected, the gas valve will close and the ignition
module will attempt ignition again (up to two more
times, for a total of three attempts.) If all three
attempts fail, the ignition control will lock out.
If ame is sensed, the burner will continue to
re as long as there is a call for heat, and none of the
safety circuit is interrupted.
If there is a call for stage 2 on a 2-stage unit, that
valve will be energized.
If there is a loss of ame signal during a
successful ring sequence, the ignition control will
remove power from the gas valves, and then attempt
to light up to two more times. If successful, the Brute
Deluxe will re normally. If unsuccessful, the ignition
control will lock out.
When the call for heat is satised, the gas
valve(s) closes, and the blower starts a 45 second
post-purge, and the pump starts the post-purge (where
applicable).
6.E Ignition Control Reaction to Air Flow
/ Blocked Vent Pressure Switch
Air ow and blocked vent status are continuously
monitored by the Brute Deluxe ignition control, at the
control’s PSW terminal.
At the start of an ignition sequence, if the ignition
control sees power at PSW for 30 seconds, but the
combustion blower has not yet been energized by the
control (F1 and F2), the ignition control will remain
in this fault mode, with the blower o. If the power to
PSW is removed while there is still a call for heat, the
ignition sequence will start again, but the main valves
will not be energized until PSW sees power during the
ignition sequence.
If the PSW signal is lost while the Brute Deluxe
is ring, the control will immediately de-energize the gas
valve terminal (MV). The blower will remain on for
the post-purge period (45 seconds), and the control
will continue to monitor the PSW input. If the signal
is detected during the post-purge period, a normal trial
for ignition will begin, starting with the 15-second
pre-purge. If the signal is not detected during the post-
purge, the control will lockout with the blower o.
6.F Operating the Burner and Set-Up
6.F.1 Set-Up for 0 to 2500 Feet Altitude
The setup must be checked before the unit is put
in operation. Problems such as failure to start, rough
ignition, strong exhaust odors, etc. can be due to
improper setup. Damage to the Brute Deluxe resulting
from improper setup is not covered by the limited
warranty.
1. Using this manual, make sure the installation
is complete and fully in compliance with the
instructions.
2. Determine that the appliance and system are lled
*1 Difference between the temperatures at which the two switches
make R-W. Adjustable from 3°F to 10°F (1.7°C to 5.6°C).
*2 Two DPDT switches operate in sequence. Each switch
differential is fixed at approximately 3°F (1.7°C).
Figure 18. Two stage aquastat