gized by a 120 VAC signal from
43.Once the ignition module determines that the hot surface igniter has heated up and operating prop- erly, a 24 VAC signal is output from pin GV on the module.
44.24 VAC signal is received at gas valve 1 thus ener- gizing it.
45.The stage 1 LED on the status display board is now illuminated.
46.The coil of relay
47.The gas coming through the burners should ignite from the heat of the hot surface igniter and the flame should carry over from one burner to the other burners of stage 1. The remote sensor is now trying to sense the flame. If the flame is not sensed within 4 seconds, the ignition module will shut down gas valve 1 and retry the hot surface igniter. During ignition retry, the heater must per- form a
48.If the ignition module locks out, a signal will be sent to the Universal Diagnostics Board to indicate an ignition fault.
49.When power is sent to gas valve 1 it is also sent to time delay relay 1
50.After the
51.After closure of the stage 2 contacts Gas valve 2 is energized.
52.The stage 2 LED on the status display board is now illuminated.
53.Power is applied to pin 5 of the stage 3 connec- tions on the CPW board.
54.After closure of the stage 3 contacts, power is applied to
55.After a 5 second countdown
56.Gas valve 3 then receives 24 VAC and is ener- gized.
57.The stage 3 LED on the status display board is now illuminated (end of sequence for 992B).
58.Power is applied to pin 7 of the stage 4 connec- tions on the CPW board.
59.After closure of the stage 4 contacts, power is applied to
60.After a
61.Gas valve 4 (solenoid valve located in the front air plenum) then receives 24 VAC and is energized.
62.The stage 4 LED on the status display board is now illuminated.
63.The heater is now operating at full fire.
Models 1532B – 1802B
1.The black (hot) wire lead goes directly to the main power switch. This black toggle switch is located at the middle front of the control compartment.
2.When the main power switch is placed in the “ON” position, 120 VAC is applied to the 120 VAC termi- nal block on the circuit board and the 120/24 VAC transformer is powered.
3.120 VAC is waiting at the N.O. contacts of the Economaster II pump delay.
4.Terminals L1 and F1 of the ignition module are powered with 120VAC.
5.120 VAC power is also applied to the control power connector on the circuit board.
6.120 VAC power is waiting at the N.O. contacts of
7.The 120/24 VAC transformer outputs 24 VAC.
8.24 VAC is sent to pin L1 of the low water
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