Honeywell T7147 User Manual

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T7147 REMOTE SENSOR AND OVERRIDE MODULE
63-4065—1
6
OPERATION
Sensor
The remote sensor control element is a negative temperature 
coefficient (NTC) thermistor. As room temperature increases, 
the resistance of the thermistor decreases. As room 
temperature decreases, the resistance of the thermistor 
increases. The T7300 detects the thermistor resistance 
change and controls the space temperature by sequentially 
staging the heating/cooling equipment on and off.
NOTE:
The T7047C1025 uses the same sensor element.
3 Hour Occupied
When correctly wired, pressing the 3 Hour Occupied key 
sends a signal from the T7147 to the T7300/Q7300. Upon 
receipt of this signal, the T7300/Q7300 proceeds into the 
3 Hour Occupied override. In response, the T7300/Q7300 
sends a signal back to the T7147 to turn on the 3 Hour 
Occupied LED. The 3 Hour Occupied LED remains on for 
the duration of the 3 hour override.
NOTE:
For additional details, consult the T7300/Q7300 
Specification sheet, form 63-4038.
3 Hour Setpoint Adjust
When wired correctly, pressing the 3 Hour Occupied key, 
followed by the Warmer or Cooler key sends a signal from the 
T7147 to the T7300/Q7300. The T7300/Q7300, upon receipt 
of this signal, proceeds into the 3 Hour Setpoint Adjust 
override. In response, the T7300/Q7300 sends a signal back 
to the T7147 that turns on the 3 Hour Occupied LED and the 
appropriate Warmer or Cooler LED. The 3 Hour Occupied 
LED and Warmer or Cooler LED remains on for the duration 
of the 3 hour override.
This override may be performed at any time, regardless of 
whether the thermostat system is operating in the occupied 
or unoccupied mode.
NOTES:
For additional details, consult the T7300/Q7300 
Specification sheet, form 63-4038.
Premature exit from either override can be 
achieved by pressing the 3 Hour Occupied key 
again. The T7300 then returns to normal operation.
CHECKOUT
1.
Allow the sensor to stabilize to ambient conditions 
before taking a resistance measurement. The sensor 
resistance measurement should be in accordance with 
the device temperature curve (see Fig. 2).
2.
Check operation of the 3 Hour Occupied key:
a. Press the 3 Hour Occupied key once.
b. The LED above the key turns on.
3.
Go to the T7300 thermostat and check it to see that the 
display arrow indicator points to 3 Hr Occupied.
4.
On models with Warmer and Cooler keys:
a. Press the Warmer key once.
b. The LED above the Warmer key comes on.
c. Press the Cooler key.
d. The LED above the Warmer key turns off and the 
LED above the Cooler key turns on.
e. Press the 3 Hour Occupied key once.
f.
The LED above this key turns off, as well as those 
above either the Warmer or Cooler keys.
5.
Go to the T7300 thermostat and check to see that the 
arrow indicator on the display no longer points to 3 Hr 
Occupied
 and has returned to its currently programmed 
occupied or unoccupied period.
NOTE:
If the T7147 does not check out, review the 
wiring and connections between the Q7300 
and the T7147. Replace the T7147 if wiring 
continuity checks out. If the new T7147 does 
not check out, replace the Q7300.
6.
Check operation of the complete control system as 
directed in the T7300/Q7300 Specification sheet, form 
63-4038.