Ramp Rates (Commercial Use); Economizer And Time Of Day (Tod) Operation - Honeywell TH8321 Product Data

VISIONPRO® 8000 SMART THERMOSTAT

Ramp Rates (Commercial Use)

When the ramp rate is set to Off, the thermostat begins
recovery at the scheduled time.
When a ramp rate is set, recovery begins early to reach the
setpoint by the program time. Based on your recovery ramp
setting and how far the thermostat is set back, the
thermostat determines how early to turn on the system.
If an outdoor sensor is installed, you can set outdoor
temperatures for mild, cold and hot days in your region. By
setting these outdoor temperatures, the thermostat will
automatically adjust the ramp rate based on outdoor
conditions. This allows the thermostat to save energy by
starting recovery at the optimum time as outdoor
conditions change.
NOTE: The thermostat uses an adjustable ramp rate
when the thermostat is setup for commercial. This
allows the thermostat to recover on time during
changing conditions (occupancy changes, tem-
perature overrides, load conditions, opening/clos-
ing of doors etc) which are common in commercial
applications.
Fig. 216.
Fig. 217.
33-00096—04
Economizer and Time of Day (TOD)
Operation
Economizer
The thermostat controls an economizer module to provide
ventilation during occupied periods and free cooling when
outdoor conditions are favorable. In some climates the
cooling system may run several hours when it may not be
required to maintain indoor comfort. When outdoor
conditions are favorable, ventilation with outdoor air can
achieve the same level of comfort at lower cost. Table 5
explains how the Economizer Module is controlled by the
thermostat.
The thermostat works with the W7220, W7212, W7213 and
W7214 Economizer Modules for both heat pump and
conventional systems.
Table 5. Economizer Operation.
Thermostat Mode Equipment Operation
Occupied Heat/Cool/Fan
running
Occupied Heat/Cool/Fan
temporarily running
Occupied Heat/Cool/Fan NOT
running
Occupied Heat/Cool/Fan NOT
temporarily running
Pre-occupancy Fan running
purge
Unoccupied Cooling system
running
Unoccupied Cooling system
temporarily running
Standby Cooling system
running
Unoccupied Cooling system NOT
running
Unoccupied Cooling system NOT
temporarily running
Standby Cooling system NOT
running
Non- Fan running
programmable
Non- Fan NOT running
programmable
* If ISU 222 "Economizer fault FDD" is set to "no" then the A-
L/A is used for economizer control. If ISU 222 "Economizer
fault FDD" is set to "yes" then the U1 contacts are used for
economizer control.
80
A-L/A
Terminal or U1
Contacts. *
A-L/A
energized or
U1 contacts
closed. *
A-L/A NOT
energized or
U1 contacts
open. *
A-L/A
energized or
U1 contacts
closed. *
A-L/A NOT
energized or
U1 contacts
open. *