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ECH16-7/10kW-P VOLTAGE
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ECH16-7/10kW- P VOLTAGE SEQUENCE OF OPERATION
NOTE - Call for heat is first stage heat for CHA16 units and second stage heat for CHP16/20 units.
1- On a call for heat, thermal heat relay K32 and K33 are
energized. Within 1-110 seconds, contacts K32-1 and
K33-1 close followed by K32-2 and K33-2.
2- When either K32-1 or K33-1 closes, nothing happens
as indoor blower is aleady energized from first stage
heat call.
3- When K32-2 closes, heating element HE1 is enerĆ
gized.
4- When K33-2 closes, heating element HE2 is enerĆ
gized.
5- When heating demand stops, heat relays K32 and K33
de-energize. Heating element HE1 and HE2 de-enerĆ
gize immediately.