Answer to Question 1
With the system switch in the heat position, the heating thermostat closes when the room temperature drops. This initiates a call for heat, creating a path from the Red side of the transformer to the W terminal on the thermostat, through the limit and roll out switches to the ignition control on line 14. The ignition control energizes the draft fan relay coil (DRF line 14), closing the DFR contacts, which energize the draft fan motor (DFM line 3). The draft fan motor operates for 60 seconds Operation of the draft fan motor causes the draft pressure switch (DPS) to close line 13. The ignition control energizes the ignition relay coil (IR line 16), closing its contacts and energizing the igniter, line 1. The igniter is energized for 60 seconds before the gas valve is energized. The gas valve is energized and the flame rectification circuit looks for the presence of flame, line 12. If flame is sensed, the gas valve remains energized and the igniter is de-energized. The heating fan relay coil
Answer to Question 2
The W terminal of the thermostat energizes the sequencer coil. Sequencer S1 contacts close to energize heater 1 and the blower motor. Sequencer S2 closes to energize heater 2
Operational Control
The Olestra study followed a sequence of steps
The cube of insulating material shown in the figure has one corner at the origin. Each side of ...
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