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Sequence of Operation - EHA 7.5, 15, 22.5, 30, 45, 60 kW - Y and G, J, M
NOTE: This sequence of operation is for all Electric Heat
kW ratings Y through J voltages. Each step of operation
is numbered and can be followed in sequence on the di-
agrams. Operation for G, J, and M voltages will be the
same.
HEATING ELEMENTS:
1 - Terminal Strip TB3 is energized when the unit
disconnect closes. TB3 supplies line voltage to
electric heat elements HE1 through HE6. Each
FIRST STAGE HEAT:
2 - Heating demand initiates at W1 in thermostat.
3 - 24VAC W1 signal is routed from the thermostat
4 -
energized.
SECOND STAGE HEAT:
Heating demand initiates at W2 in thermostat.
6 - 24VAC W2 signal is routed from the thermostat
through TB1 and P2-7. Electric heat contactor K16
is energized.
7 -
HE3 and HE4 electric heat is energized.