Bryant 604B, Руководство пользователя

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SEQUENCE OF OPERATION
When power is supplied to unit, the transformer (TRAN) is
energized.
On units with crankcase heater, heater is also energized.
Cooling — With the thermostat subbase in the cooling position,
the thermostat makes circuit R-O. This energizes the reversing
valve solenoid (RVS) and places the unit in standby condition for
cooling.
As the space temperature rises, the thermostat makes, closing
circuit R-Y. A circuit is made to contactor (C), starting the
compressor (COMP) and outdoor-fan motor (OFM). Circuit R-G
is made at the same time, energizing and starting the indoor-fan
motor (IFM).
When the thermostat is satisfied, contacts open, deenergizing C.
The COMP and OFM stop, and the IFM stops after a preselected
time delay.
Heating — On a call for heat, thermostat makes circuits R-Y and
R-G.
A circuit is made to C, starting COMP and OFM. Circuit R-G also
is completed, energizing IFR and starting IFM after the selected
time delay.
Should room temperature continue to fall, circuit R-W is made
through second-stage thermostat bulb. If optional electric heat
package is used, a relay is energized, bringing on first bank of
supplemental electric heat. When thermostat is satisfied,
contacts open, deenergizing contactor and relay; motors and
heaters deenergize. The IFM is controlled by the Easy Select™
board.
Defrost — Defrost board (DB) is a time and temperature control,
which includes a field-selectable time period (Dip switch 1 and 2
on the board) between checks for defrost (30, 60, 90, or 120
minutes). Electronic timer and defrost cycle start only when
contactor is energized and defrost thermostat (DFT) is closed.
The defrost board is also equipped with a 3rd dip switch for
selecting Quiet Shift operation. The Quiet Shift operation turns
compressor off at defrost initiation and termination. Unit is
factory shipped with quiet shift turned off.
Defrost mode is identical to cooling mode, except outdoor fan
motor stops and a bank of optional electric heat turns on to warm
air supplying the conditioned space.
NOTES:
1. Compressor time delay occurs through the defrost control
board.
2. Defrost control board has built in 5 minute compressor delay:
once the compressor has started and then stopped, it cannot be
restarted again until 5 minutes have elapsed.
3. Variable Speed Blower — The indoor blower operation with a
call for fan operation (G) in either cooling or heat pump heating
(compressor) modes will perform by the on/off delay profile
selected at start up on the Easy Select™ board.
CONTROLS