Y1 DEMAND
OPEN
SERVICE
2
REQUIRED
OPEN
Figure 31. High Pressure Switch (S4) Sequence of Operation (All Versions)
31-5000746 Rev. 0
HIGH
PRESSURE
CLOSED
SWITCH (S4)
HIGH
PRESSURE
OPEN
SWITCH (S4)
CONTACTOR
DE-ENERGIZED
1. The thermostat will terminate demand when the contactor is
de-energized. If demand is satisfied when alarm is not active, the
5-strike counter will reset.
2. Lockouts can be reset by cycling power off to the outdoor control's
ANTI-SHORT
(A175) R terminal.
CYCLE TIMER
BEGINS
INCREMENT
5-STRIKE
1
COUNTER
LED ALERT
CODE / OR
MODERATE
ALERT 412
DISPLAYED
ANTI-SHORT
CYCLE TIMER
ENDS
HIGH
PRESSURE
CLOSED
SWITCH (S4)
WAITING FOR
PRESSURE
CLOSED
SWITCH TO
CLOSE
TOP CAP
SWITCH (S173)
CLOSED
5-STRIKE
COUNTER
REACHES 5
WITHIN A SINGLE
Y1 DEMAND
HIGH
PRESSURE
SWITCH (S4)
LOCKOUT
LED ALERT
CODE / OR
CRITICAL
ALERT 413
CLEARED
LED ALERT
CODE / OR
MODERATE
ALERT 412
DISPLAYED
Page 61
CONTACTOR
CLOSED
ENERGIZED
SERVICE
2
REQUIRED
NORMAL
OPERATION