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X−WIRING SCHEMATIC AND OPERATION SEQUENCE
A−CBX32MV − 208/230V SINGLE PHASE − SEQUENCE OF OPERATION
1. Line voltage is routed to transformer T1 and blower
motor B3.
2. T1 supplies 24VAC to terminal strip TB1, which
supplies 24VAC to the indoor thermostat and electric heat,
if used.
HEATING
3. When there is a call for heat, W1 of the thermostat
energizes the electric heat relay K32 (covered in the
electric heat section). After K32 closes, blower relay
K20−1 is energized.
4. Blower motor B3 is energized on heating speed after
K20−1 closes (see electric heat).
5. Economizer relay K20−2 (if used) is energized after K32-1
closes (see electric heat section).
6. K20−2 closes energizing the economizer with 24VAC.
COOLING
7.
See Table 16 for cooling sequence of operation.
