Power The Thermostat - EWC Controls EWT-3102 User Manual

POWER THE THERMOSTAT

You can choose from three methods to power the thermostat Batteries
· only (AA alkaline).
· 24 VAC common wire only.
· 24 VAC common wire with battery backup (AA alkaline).
Wiring 24 VAC Common
· Single-Transformer System:
Connect the common side of the transformer to the C screw terminal of the thermostat
wallplate. Leave the metal jumper wire in place between RC and R.
·Two Transformer System:
Connect power side of "Cooling" transformer to RC terminal. Remove factory installed
jumper. Connect common side of "COOLING" transformer to the compressor contactor,
relay, etc. Connect power side of "HEATING" transformer to the R terminal. * Connect
the common side of the Heat relay to the C terminal.
EWT-3102 / EWT-3103 Touchscreen Programmable Thermostat
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