Geothermal Radiant Heat; Heat Pump And Backup Heat Operation - Honeywell TH8320R1003 Vision Pro 8000 Product Data

HEAT PUMP AND BACKUP HEAT OPERATION

Heat pump with outdoor temperature lockouts
Outdoor temperature lockouts are optional. See Installer Setup options (ISU 312).
Alert Light - General
An alert light is located in the lower right corner of the
thermostat. See Fig. 77 and 78. This light turns red when an
alert is active or the system is set to the Em. Heat mode. The
alert light is on continuous when the thermostat is system
powered (C Wire) and flashes if the thermostat is battery
powered.
Alert Light - Heat Pump Systems
When the L terminal is wired to a compressor monitor and it
receives 24 volts, the alert light on the thermostat will turn red
to indicate a system problem. The thermostat monitors 24 volts
on the L terminal in Heat, Cool and Auto modes.
Alert Light - Emergency Heat Indication
When the thermostat is setup for a Heat Pump with an
Auxiliary Heat source, the alert light will turn red when the user
sets the system to the Em. Heat mode. It is normal for the alert
light to turn red in the Em. Heat mode to remind the user that
they are currently operating their Emergency Heat and the
Heat Pump is locked out.

Geothermal Radiant Heat

The thermostat can be setup to control Geothermal Radiant
Heat, Geothermal Forced Air Heat and Backup Heat, all from
one thermostat. The thermostat stages the equipment starting
with the Geothermal Radiant Heat followed by Geothermal
Forced Air Heat and then Backup Heat as needed to maintain
the desired temperature. The thermostat allows you to set
differential temperature settings between each stage if you
want the equipment to stage a certain way (see ISU 303 to ISU
309, page 26). For additional wiring diagrams, see "Wiring"
beginning on page 116.
NOTE: To turn off Radiant Heat during the shoulder sea-
sons, install an outdoor reset control and connect
to the Radiant Heat or switch the thermostat to
Emergency Heat mode.
Electric Backup Heat (Backup Heat Allowed
to Run with Heat Pump)
HEAT MODE
The thermostat turns on Backup Heat only when the indoor
temperature drops to the selected Backup Heat Droop setting
or the Backup Heat Upstage Timer expires (whichever occurs
first). Geothermal Radiant Heat and Geothermal Forced Air
Heat stay on when the Backup Heat turns on.
EMERGENCY HEAT MODE
The thermostat turns on the Backup Heat to maintain the
desired temperature setting. Geothermal Radiant Heat and
Geothermal Forced Air Heat are not used.
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VISIONPRO 8000 WITH REDLINK™
68-0312—01