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T7200/T7300/Q7300
OPERATION
NOTE: These unoccupied defaults are only used if an unoc-
cupied start time is entered or the CONT UNOC key is
pressed. Immediately following initialization, the user
can enter new setpoints to be used in place of the default
values.
If the battery backup was operating during a power
failure, and 24 Vac power comes back on, the user-entered
time and temperature program saved in memory is used. If
24 Vac is lost, and no battery backup exists, the default
temperatures is placed into memory when the power comes
back on. These default values are then used for temperature
control.
Occupied
When the thermostat is operating in the occupied mode,
the temperature is controlled to the occupied heat or cool
setpoint. The normally open (A1) auxiliary relay contacts
are closed and the normally open contacts (A3) auxiliary
relay contacts are opened during the occupied modes (if the
subbase being used has this option). The fan operates as
follows:
• No switching subbase used: Operation of the fan is
continuous (fan always energized) unless the fan op-
tion switch on the back of the T7300 (#3) is set to
intermittent (cycles with Y1 or W1).
• Switching subbase used: Q7300 fan switch can be set
to ON (always energized) or AUTO (cycles with Y1
or W1).
NOTE: If subbase configuration switch no. 4 (on any Q7300
conventional subbase) is set to the ON position, the fan
cycles on a call for cooling only; switch no. 4 has no effect
on heat pump subbases (Q7300C, D, F).
Unoccupied
When the thermostat is operating in the unoccupied
mode, the temperature is controlled to the unoccupied heat
or cool setpoint. The auxiliary relay contacts is open and the
fan operates as follows:
• Switching or non-switching subbase used: Fan is al-
ways be intermittent (cycles with Y1 or W1). See
NOTE for OCCUPIED.
Conventional System
RECOVERY FROM UNOCCUPIED
Intelligent Recovery™ is a Honeywell trademark for
the way the thermostat controls the heating and cooling
equipment during recovery from unoccupied to occupied
setting. During recovery, the control point ramps up at the
rate of 5°F (3°C) per hour rather than jumping from the
energy savings setting to the comfort setting all at once.
This provides additional energy savings.
When the Intelligent Recovery™ is used in the heating
mode, the control point raises 5°F (3°C) per hour, maximiz-
ing the use of the more economical first stage heat to bring
the sensed temperature to the desired comfort setpoint. This
minimizes using the typically more expensive second stage
heat.
63-4038—7
The advantages are:
• Comfort setting is achieved at the programmed time
and maintained regardless of weather conditions; oc-
cupants are comfortable.
• Drafts from low temperature discharge air are mini-
mized during occupied periods.
• The thermostat automatically uses the more economi-
cal first stage of heat as the primary heat source during
heat mode recovery, avoiding the use of the expensive
second stage heating.
• Comfort and energy savings can be achieved in both
heating and cooling.
• The thermostat reduces heat cycling, extending equip-
ment life.
Heat Pump Operation
The T7200 is fixed for either heat pump or conventional
control applications. The T7300 is configurable for either
heat pump or conventional applications, depending on the
subbase used. Additional information is required when
configured for heat pump.
The heat pump mini-jumper (located on the back of the
thermostat) places the thermostat into the heat pump mode.
Refer to the Installation section.
O AND B TERMINALS FOR HEATING
OR COOLING CHANGEOVER
The Q7300C and F controls heat pump changeover. The
Q7300D is only used in a heat pump application when the
heat pump controls the reversing valve changeover. See
Table 8 for the operation of the O and B terminals on the
Q7300C and F.
TABLE 8—OPERATION OF THE Q7300
O AND B TERMINALS.
System Switch
Heat
Cool
a
Auto (Heat)
b
Auto (Cool)
Emergency Heat
Off
a
When the system is calling for heat or is de-energized, but
the last function was heat.
b
When the system is calling for cool or is de-energized, but
the last function was cool.
c
When the last function was heating, the operation is the
same as Auto (Heat). If the last function was cooling, the
operation is the same as Auto (Cool).
RECOVERY FROM UNOCCUPIED
The heating recovery ramp is 3°F per hour, which
differs from the 5°F per hour for conventional systems. The
3°F degree difference helps the system use the economical
heat pump more and the expensive auxiliary heat less. The
cooling ramp is 5°F, the same as conventional systems.
16
O
B
Open
Closed
Closed
Open
Open
Closed
Closed
Open
Open
Closed
c
c
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