12F With Svr Relays; All Units - Bryant Legacy Series Installation, Start-Up And Service Instructions Manual

WATCH
YOUR
SUCTION
RISERS
LIQ INJ BULB
TO SUCTION LINE
SOLENOID
VALVE
Fig. 31 — Location of Hot Gas Bypass in 569J*12F
569J*12F with SVR Relays
With no thermostat demand, there will be no voltage at LVTB-A1;
HGBP SOLENOID is de-energized and solenoid valve remains
SUCTION LINE
HOT GAS
DE-SUPERHEAT
HOT GAS LINE
CHAMBER
HOT GAS BULB
TO SUCTION LINE
AND INSULATE
SCHRADER VALVE
AT BOTTOM
COMPRESSOR
Fig. 30 — Hot Gas Bypass Option
HOT GAS BYPASS
FACTORY INSTALLED
OPTION
30
EVAPORATOR
COIL
closed, preventing bypass vapor from the desuperheating tank to
enter the suction line at the compressor.
On a thermostat call for first-stage cooling, LVTB terminal Y1
is powered; when CADM1 is satisfied, compressor contactor
C1 and Solenoid Valve Relay SVR1 are energized. SVR1 con-
tacts close, providing 24-v to LVTB terminal A1, then through
HGBP RELAY NC contacts to HGBP SOLENOID. HGBP so-
lenoid valve opens, allowing bypass vapor from the desuper-
heating tank to enter the compressor suction port.
If thermostat calls for second stage cooling, LVTB terminal Y2
is powered; when CADM2 is satisfied, compressor contactor
C2, Solenoid Valve Relay SVR2 and HGBP RELAY are ener-
gized. HGBP RELAY NC contacts open, de-energizing the
HGBP SOLENOID; solenoid valve closes, blocking bypass
vapor from the desuperheating tank and unit runs at full cool-
ing capacity.
The model 569J*12F also includes the 32LT Motormaster low
ambient control as a standard feature. Refer to Appendix C for
information on the Motormaster control.

All Units

If either the Low Pressure Switch or High Pressure Switch
opens while thermostat output Y1 or Y2 remain energized, the
compressor contactor is de-energized, the compressor stops
and liquid line solenoid is de-energized (valve closes). CADM
initiates a TRIP event (cooling demand sensed at CADM ter-
minal Y but no current is measured at T1, T2, T3 motor sen-
sors); CADM relay opens and RED LED is illuminated. TRIP
condition maintains lockout of compressor operation until
CADM is manually reset. Reset CADM by cycling unit main
power.
CONDENSER
COIL