Honeywell CHRONOTHERM IV T8665A - Manual (Page 14)

14 69-1536–3
Setting the System Key
Press the System key until the desired
system (Heat, Off, Cool, or Auto) displays.
Heat: The thermostat controls the heating.
Off: Both the heating and cooling are off.
Cool: The thermostat controls the cooling.
Auto: The thermostat automatically changes
between heating and cooling operation,
depending on the indoor temperature.
Thermostat will satisfy system demand
on a first call basis. For example, if
zone 2 (any zone) is calling for heating
and then zone 1 (any zone) asks for
cool – the system will satisfy zone 2
before turning on the cool for zone 1.
System
Setting the Fan Key
Press Fan key until the desired mode
(On or Auto) displays:
On: Fan operates continuously.
Auto: Fan operates only when heating
or cooling.
displays when the thermostat is
calling for the fan in this zone.
NOTE: The thermostat may delay
turning on the fan until another zone
has completed its call for heat or cool
before initiating the fan call for this zone.
Fan
ZONING
ZONING