Taylor C832 Service Manual page 75

Circuit Overview
1. When a MCB calls for heat the MCB sends a
24 volt signal to TH/W. This initiates the ignition
sequence.
2. The IDC then checks the position of the
pressure switch. At this stage of the sequence
the pressure switch should be open.
3. Once the open position of the pressure switch
is verified the IDC sends 220VAC to the blower
motor.
4. Once the blower is energized the IDC
re­checks the pressure switch to ensure it is in
the closed position.
5. The high voltage signal is now sent to the
electrode for ignition
6. Next V1 output is sent to the gas system's
relay. When the coil of the relay is energized
two sets of contacts are closed. The relay has
two functions in this system.
McDonald's Intelligap Grills
a. The first is a volt signal is send from the 12
IDC Output (On MCB) to contact 12 on
relay. When the relay closes the 12 volt
signal comes out of contact 8 and it sent to
J4 Pin 10.
1. The feedback to the J4 Pin 10
connection tells the board that the
system is in working order. If this
signal does not return to the Pin 10
connection the MCB will assume there
is a failure in the system, and cut
power to the IDC resulting in a
BLOWER failure.
b. The second function of the relay is to
connect L1 to the gas solenoid.
7. Once the burner lights, the IDC removes the
voltage to the electrode and monitors the 24
MCB input, pressure switch position (Closed)
and the presence of flame in the burner (Flame
Sense).
8. When the call for heat is satisfied the MCB will
cut power to TH/W.
9. The IDC will recognize the heat cycle is over
and de­energizes the gas system relay. The
IDC monitors the loss of the flame sense
signal. When the signal is lost (Flame has gone
out) the IDC de­energizes the blower motor.
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Controls and Systems