White Rodgers 1F95-1280 Wired Remote Temperature Sensing, Averaging or Weighting Remote Sensors

Models: 1F95-1280

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Wired Remote Temperature Sensing

PROGRAMMING

Wired Remote Temperature Sensing

One remote temperature sensor can be installed indoor or outdoor and connected to the thermostat by a maximum cable length of 100 meters (300 feet). Terminals +, S and - on the terminal block allow connection of the remote sensor. The thermostat must have 24 VAC Common connection to terminal C for the remote sensor to operate. The remote sen- sor can be enabled or disabled in the Installer/Confi guration menu, item 25.

When remote sensor, Remote, is selected Off (factory de- fault), no remote sensor is enabled. When remote sensor is selected On, the next step is to select the remote as indoor, Remote In, or outdoor, Remote Outdoor. If the remote is se- lected as Remote In, an additional step will be to select if the temperature shown on the display will be from the thermostat, LS On, or the remote sensor LS Off.

In normal operation, when a remote sensor is enabled the time digits of the display will alternate between the time and the remote temperature for three seconds each. Above the remote temperature will be Remote, for indoor sensor or Outdoor Remote, for outdoor sensor. If the remote sensor is an indoor sensor and the local display has been disabled, the temperature displayed as the room temperature will be the remote sensor temperature.

Sensing Range:

Outdoor temperature range is -40oF to 140oF

Indoor temperature range is 32oF to 99 oF

Averaging or Weighting Remote Sensors

The thermostat will weight or average the temperature of the indoor remote sensor with the local sensor in the thermostat for each program period. The averaging will be active only when the local sensor and the indoor remote sensor are both functional and enabled in the Installer/Confi guration menu.

When the thermostat is in the Set Schedule mode, the weight of the indoor sensor will be shown in the current temperature digits of the display. The weight will show as A2 (average and default), H4 (high) or L1 (low). Pressing theAveraging or Weighting Remote SensorsandDual Fuel Temperature Setpointkeys at the same time will change the weight for the program period. The weight of the thermostat sensor is fi xed.

In normal operation of the thermostat, the current tempera- ture displayed will be the weighted average of the local sensor and the remote sensor using the formula (local sensor weight x local sensor temperature) + (remote sensor weight x remote sensor temperature) / (local sensor weight + remote sensor weight).

Example: Local sensor temperature is 80° and the remote sensor is 70°.

If weight is selected H4, the averaged temperature of 72° will be displayed.

(1 x 80) + (4 x 70) / 5 = 72°

If weight is selected A2, the average temperature of 73° will be displayed.

(1 x 80) + (2 x 70) / 3 = 73.3°

If weight is selected L1, the average temperature of 75° will be displayed.

(1 x 80) + (1 x 70) / 2 = 75°

The example shows that the weight selected would prioritize the overall averaged temperature between the two sensors. The high weight selection caused the remote sensor to have a higher infl uence in the calculated temperature average than the local sensor and the low weight selection caused the remote sensor to have less infl uence.

Dual Fuel Temperature Setpoint

When the thermostat is confi gured for Heat Pump mode and the Dual Fuel feature is selected on, the thermostat can moni- tor the outside temperature using remote sensor F145-1378 or use software logic to determine when to switch to gas heat and shut down the compressor. This eliminates the need for a fossil fuel kit.

The user selectable temperature is called the dual fuel tem- perature setpoint, dF and is set in the Installer/Confi guration menu, items 26 or 27. With outdoor remote sensor installed and enabled (menu item 27), the dual fuel temperature setpoint can be set to a temperature of 5° through 50°. When outdoor remote sensor is not installed (menu item 27), a software logic based dual fuel number from 01 to 09 can be selected.

After the dual fuel temperature setpoint is set andManual backgroundis pressed, a delay, Cd, can be set for compressor shutdown after the auxiliary stage is energized. This delay can be set from 0 seconds to 99 seconds to minimize the time that the system may blow cooler air until the alternate source of heat comes on. Default setting for delay is 60. When setting the delay, if theManual backgroundorManual backgroundkeys are held depressed, the setpoint will increase or decrease at the rate of one degree every half second for the fi rst three seconds and double the speed after three seconds.

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White Rodgers 1F95-1280 specifications Wired Remote Temperature Sensing, Averaging or Weighting Remote Sensors, Programming