Communicating Unitary Control (Uc) Pcb - Daikin ComfortNet DX16TC Series Service Instructions Manual

PRODUCT DESIGN

Communicating Unitary Control (UC) PCB

The Communicating System Unitary Control PCB is a micro-
processor-based control for heat pump and air conditioning
condensing units with single-phase compressors up to 5 ton
capacity operating on standard residential or Delta and Wye
commercial power. The control incorporates the basic func-
tionality of existing defrost controls, outdoor thermostats,
contactors, compressor staging controls, short cycle controls,
line voltage monitors, Comfort Alert™ or CoreSense Module
(dependent upon which module you are using), two
speed condenser fan relays and the Active Protection compo-
nent of enabled thermostats. The control is designed to work
as part of a fully communicating HVAC system with 4 wires.
The control also supports legacy 24VAC thermostat inputs for
Y1, Y2, O and 24VAC outputs for RVS, W1, and L for non-com-
municating systems. Outputs include compressor power,
compressor stage select, and outdoor fan high and outdoor fan
low speed. System inputs include high/low pressure switches,
as well as thermistor inputs for outdoor coil temperature and
outdoor air temperature.
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