What is swing, and how do I set it?

By: dcahill

A thermostat works by turning your heating or cooling system on and off whenever the room temperature varies a certain number of degrees from the set-point.  This variation is the “swing”.  Your system should cycle on about 3 to 6 times per hour.

The PSD111 has 2 swing settings called: “0.25” and “0.50” (shown as degrees Fahrenheit).

The smaller swing setting of “0.25” increases the number of cycles, so room temperature is more constant.  This setting provides maximum comfort.  The larger setting of “0.50” decreases the number of cycles per hour.  You may feel a slight increase in the amount of temperature variation but this setting saves more energy.

We recommend the narrow setting which provides maximum comfort.  This is also the default value that the thermostat already has in it when it is shipped.


To change the swing setting:

  1. Take the front cover of the stat off the wall
  2. Open the thermostat and locate the jumper table on the circuit board.  J4 is the jumper that sets the swing.
  3. Look for the Row that has “J4 (Swing)”.  Look up to the top of the table to find the “Open” or “Closed” position.

“Open” position (0.25) is when only 1 of the pins is covered by little black cap.

“Closed” position (0.50) is when both pins are covered by little black cap.

The jumpers are labeled on the circuit board next to each black cap.  

        4. Identify the jumper you are looking for (JP4).  

        5. Pull the jumper cap off the pins and then place it back in the desired position.

        6. Now hit the software reset button on the front of the thermostat between the UP/DOWN buttons.  The swing setting will now be recognized.

Actual temperature variation will vary depending on the conditions specific to your home (heater size, how well insulated, etc…).  As an approximation:

Swing            Temp

Setting          Variation

0.25 =           3/4 F degrees (plus & minus) of actual room variation

0.50 =           1-1/4 F degrees (plus & minus) of actual room variation


Example:  For tightest control, set swing setting to “0.25” which gives about plus or minus 3/4 degrees F.  If you set the setpoint at 70F, the highest it should get to is about 70.75F, and the lowest it should get to is about 69.25F

On swing setting “0.50” and a setpoint of 70F, the highest it should get to is about 71.25F, and the lowest it should get to is about 68.75F.


NOTE: keep in mind that the thermostat’s display screen only shows “whole numbers” and will round up or down to the nearest degree.