Lennox EL23XCV Series Manual page 56

Y1 DEMAND
OR COOLING PRESSURE ABOVE
DEMAND
NO
PRESSURE ABOVE
SERVICE
2
REQUIRED
NO
FIGURE 28. Low Pressure Switch Emulated by Suction Pressure Transducer Sequence of Operation (All Units)
*SUCTION
YES
CUT-OUT OF
40 PSIG
SUCTION PRESSURE
ABOVE CUT-OUT
NO
CONTACTOR
DE-ENERGIZED
1.
2.
ANTI-SHORT
CYCLE TIMER
3.
BEGINS
INCREMENT
5-STRIKE
1
COUNTER
LED ALERT
CODE / OR
MODERATE
ALERT 410
DISPLAYED
ANTI-SHORT
CYCLE TIMER
ENDS
CONTACTOR
ENERGIZED
SUCTION
CUT-IN OF
90 PSIG
WAITING FOR
PRESSURE
TO RISE ABOVE
90 PSIG
NO
CONTACTOR
ENERGIZED
YES
OF 40 PSIG
The thermostat terminates demand when the contactor
is de-energized. If demand is satisfied when alarm is
not active, the 5-strike counter resets.
door control (A175) R terminal.
The suction pressure cut-out of 40 psig is ignored by the
system when the outdoor temperature is below 15°F.
5-STRIKE
COUNTER
REACHES 5
WITHIN A SINGLE
Y1 DEMAND
LOW
PRESSURE
LOCKOUT
LED ALERT
CODE / OR
CRITICAL
ALERT 411
DISPLAYED
LED ALERT
CODE / OR
MODERATE
YES
ALERT 410
DISPLAYED
YES
Page 56
SUCTION
PRESSURE
CUT-OUT IS
IGNORED FOR
90 SECONDS
SUCTION PRESSURE CUT-OUT
IS BYPASSED IF OUTDOOR
AMBIENT TEMPERATURE IS 15ºF
OR BELOW
SERVICE
2
REQUIRED
NORMAL
OPERATION
*EL23XCV does not have a low pressure switch
and LPS terminals are not jumpered. The unit has a
suction pressure transducer that emulates the low
pressure switch with a cut-out of 40 PSIG and a
cut-in of 90 PSIG.
3