Lennox XC21 Series Unit Information page 58

Y1 DEMAND
OPEN
DISCHARGE
SENSOR (RT28)
IS AT OR
BELOW 225ºF
NO
Figure 34. High Discharge Temperature (RT28) Sensor Sequence of Operation
XC21
DISCHARGE
CLOSED
SENSOR
(RT28)*
PRESSURE
OPEN
SWITCH (S4)
COMPRESSOR
1
CONTACTOR
If 5−strike counter has four or less strikes when Y1 demand
DE−ENERGIZED
is terminated or satisfied, the strike counter will reset to
zero. In a icomfort Toucht thermostat enabled setup, the
thermostat will terminate demand when the compressor
contactor is de−energized. If demand is satisfied when
COMPRESSOR
alarm is not active, the 5−strike counter will reset.
ANTI−SHORT
CYCLE TIMER
2
Lockouts can be reset by either cycling power off to the air
BEGINS
conditioner control's (A175) R terminal, or placing a jumper
on the field test pins (E33) between 1 to 2 seconds.
INCREMENT
5−STRIKE
1
COUNTER
LED ALERT
CODE / OR
MODERATE
ALERT 414
DISPLAYED
ANTI−SHORT
CYCLE TIMER
ENDS
YES
COMPRESSOR
CONTACTOR
ENERGIZED
WAITING FOR
TEMPERATURE
DROP TO OR
BELOW 225ºF
*
COMPRESSOR
CONTACTOR
ENERGIZED
HIGH
CLOSED
5−STRIKE
COUNTER
REACHES 5
WITHIN A SINGLE
Y1 DEMAND
DISCHARGE
SENSOR (RT28)
LOCKOUT
LED ALERT
CODE / OR
CRITICAL
ALERT 415
CLEARED
LED ALERT
CODE / OR
MODERATE
ALERT 414
CLEARED
Page 58
If temperature is at or above 279ºF.
SERVICE
2
REQUIRED
NORMAL
OPERATION