CONQUEST 80 - Robertshaw and Honeywell Standing Pilot Fan Control Boards; Fan Control Board; Blower off Settings - Robertshaw Standing Pilot; Blower off Settings - Honeywell Standing Pilot

ROBERTSHAWAND
HONEYWELLSTANDING
PILOTFAN CONTROL
BOARDS
Standing Pilot Low Profile furnaces
come equipped with an electronic
blower control board that controls the
on/off sequence of the blower motor.
The blower on timing is factory fixed
for consistent blower operation. The
off timing may be field adjusted at the
fan control board. This control also
includes a relay to operate the
induced draft blower and a low
voltage terminal board for thermostat
connections. The fan control board is
located inside the electric box in the
blower compartment.
When the installer wires the furnace,
115-volt power automatically powers
the board. It comes in through the
9-pin junction plug. Components such
as the induced draft blower, limits,
over temperature switches, pressure
switch, and gas valve connect to the
board through the junction plug. The
transformer primary connects to
terminals "S" and "N." The
transformer secondary connects to
terminals "C" and
"X."
Along the side are thermostat con-
nections. The blower motor connects
to the heat and cool terminals on the
integral relay. Any unused motor
leads connect to terminals M1 and
FIGURE 51
BLOWER OFF SETTINGS -
ROBERTSHAW STANDING PILOT
MODEL RBC-1
90 SEC.
D □
□
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c--i
120 SEC.
150 SEC.
LJ
0
[J
"'
180 SEC.
u,
i
ROBERTSHAW
UPFLOW MODELS
M2. The motor common wire
connects to terminal "N."
The board automatically starts the
blower 20 seconds after the gas
valve opens. It is factory set to stop
the blower 120 seconds after the heat
call ends. On the Robertshaw board
a set of terminals and jumper plug
varies this off timing from 90 seconds
to 180 seconds. Moving the jumper
plug to another set of terminals
FIGURE 50
FAN CONTROL BOARD
changes the off timing. DO NOT
MISPLACE THIS JUMPER PLUG.
If the jumper is not in place, the
indoor blower will not shut off.
The Honeywell board is similar to the
Robertshaw control. Only the
Honeywell uses two screw switches
marked "A" and "B" to vary the blower
off timing from 90 to 180 seconds.
Changing the position of the screw
switches changes the off timing.
FIGURE 52
BLOWER OFF SETTINGS -
HONEYWELL STANDING PILOT
HONEYWELL
OOWNFLOWMODELS
MODEL ST9101A
90 SEC. 120 SEC. 150 SEC. 180 SEC.
58