Installation - Honeywell T7984 A Product Data

Table 2. Option Settings
Parameter Selection
Reheat Time Fast (7.5 min.); or Normal
Constant (15 min.)
Zero Energy 3°F (1.5°C); or 5°F (3°C)
Band
Setpoint Heating; Cooling or H/C
Definition midpoint
Night 5°F (3°C) heat/cool offset, or
Setback 10°F (5°C) setback / cooling
shutdown
Main Sensor Remote or internal
Fig. 1. Dimensions in inches (mm)

INSTALLATION

Location
Install the thermostat about 5 ft. (1.5 m) above the floor in an
area with good air circulation at average temperature
conditions.
Do not install thermostat where it may be affected by:
• drafts, or dead air spots behind doors and in corners.
• hot or cold air from ducts.
• radiant heat from sun or appliances.
• concealed pipes and chimneys.
• unheated (cooled) areas such as an outside wall behind the
thermostat.
Mounting
The thermostat can be mounted directly on the wall with or
without a wallplate or a standard single gang electrical box, or
double gang with adaptor plate (accessory part 272846).
T7984 A,B,C ELECTRONIC MODULATING CONTROL THERMOSTATS
T7984 Model
A B C
• Wiring
Typical wiring connections are shown in Fig.2 to Fig.7. Wiring
connections may be made to the screw terminal block with 2-
• •
18AWG or 1-14AWG, solid or stranded copper wires. Connect
the system wires to the thermostat terminals. Push excess wire
back into hole. Plug hole to prevent drafts.
• •
Auxiliary screw terminal strip may be used in a junction box
• •
when the application requires multiple wires to be brought
down at the thermostat. This can make troubleshooting,
startup and servicing easier.
• • •
DIP Switch Settings
T7984 thermostats must be configured for proper operation by
setting DIP switches.
T7984B
Reheat output control action: 7.5 or 15 minutes.
T7984B,C
Zero energy band (ZEB): 3°F (2°C) or 5°F (3°C)
Setpoint adjustment: cooling,centred, heating centred with limit
override for commissioning.
Night setback amount: see Table 2 for complete listing of
option settings.
T7984A,B,C
Main sensor, internal or remote.
ON = 1
OFF = 0 1 2 3 4 5 6
3
CAUTION
Disconnect power supply to prevent electrical
shock or equipment damage.
Table 3. T7984 DIP Switch Definition
OUTPUT 2 ON/OFF CPH
For more information, see on/off output cycle per hour application note.
CYCLES/HOUR S1
FAST 8 CPH 1
SLOW 4 CPH 0
ZERO ENERGY BAND
ZEB S2
5°F (3°C) 1
0
3°F (1.5°C)
SETPOINT DIAL DEFINITION
For more information, see setpoint dial definition & setpoint limitation application note.
DEFINITION S3
1
75°F OVERRIDE
HEATING DIAL 0
COOLING DIAL 1
CENTERED HC 0
DAY/NIGHT SETBACK
HEAT SETBACK COOL SETUP
20°F (10°C)
10°F (5°C)
5°F (3°C) 5°F (3°C)
REMOTE SENSOR
On model T7984A, switch S7 & S8 are not used.
MAIN SENSOR S6
LOCAL INTERNAL 1
REMOTE SENSOR 0
T7984B only
It is possible to fix the number of times per hour the on/off
output will be energized.
T7984B & C only
On models which have 2 outputs, 1 for cooling and 1 for
heating, it is possible to adjust the zero energy band value
(dead band between heating and cooling endpoints).
T7984B & C only
S4
Models with cooling and heating outputs
1 » Setpoint dial centered, 75˚F limitation not active.
» Setpoint dial defined as heating, 75˚F limitation active.
1
0 » Setpoint dial defined as cooling, 75˚F limitation active.
0
» Setpoint dial centered, 75˚F limitation active.
T7984B & C only
Night mode setpoints can be adjusted
S5
to different values depending on the
1
application.
0
T7984A, B & C
For duct return air or remote room sensor control only.
Do not use remote sensor in supply or discharge air
control applications.
95C-10815–2