Honeywell EXCEL 5000 User Manual page 52

ALPHABETIC REFERENCE
Off Time Calculation
74-5577–33 (US)
EN2B-0184 GE51 R0518 (Europe)
DUC calculates off time by comparing zone temperatures X1 and X2 with the
comfort range (P3). DUC calculates the comfort limits around the setpoint (X4) with
the following formulas:
Upper comfort limit = X4 + P3
(setpoint plus comfort range)
Lower comfort limit = X4 - P3
(setpoint minus comfort range)
If the minimum zone temperature (X2) is less than the lower comfort limit or if the
maximum zone temperature (X1) is greater than the upper comfort limit, off time is
zero. A zero off time lets the system operate without interruption to reach the
setpoint as quickly as possible.
If the minimum zone temperature (X2) is equal to the lower comfort limit or if the
maximum zone temperature (X1) is equal to the upper comfort limit, DUC cycles the
system with minimum off time (P5).
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EXCEL CARE CONTROL ICONS