SECTION 9: WIRING

9.4 Ladder Wiring Diagram

120 VAC

FLUE BLOWER

TRANSFORMER

GAS VALVE

FLAME

SENSOR

ELECTRODE

3 2 1

6 5 4

FLAME IGNITION MODULE

SPARK

PRESSURE SWITCH

LIMIT SWITCH LIMIT SWITCH (UHD 300, 350, 400 ONLY)

MANUAL RESET LIMIT SWITCH (UHD 75 - 125 ONLY)

THERMOSTAT CONNECTION

FLUE BLOWER

IMPORTANT:

For field wiring into service junction box, or if any of the original wire supplied with the heater

must be replaced, it must be replaced with wiring material having a temperature rating of at least 105 °C (221 °F) and 600 V. For supply connections, use No. 14 AWG or larger wires.

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Image 27
Roberts Gorden UHD[X][S][R] 125 Ladder Wiring Diagram, Flue Blower Transformer GAS Valve Flame Sensor Electrode