STR-150 Calibration Feature

[Product_Support]

Issue

In the past there was no way to calibrate the space temperature from a STR-150 when used with a Xenta 121 FC/HP. 

Environment

• STR-150
• Xenta 104A
• Xenta 120
• Xenta Programmables

Cause

Any calibration applied to the temperature of a STR-150 had to be done downstream of the stat in the controller. In the past when the STR-150 room stat was wired up to a Xenta 121 there was no way to calibrate the space temperature as the Xenta 121 FC/HP had no kind of Temp Offset in the controller.

Resolution

Starting with version 1.4 (released September 2013) of the STR-150, there is a calibration feature built into the stat. This feature allows the calibration to be applied before the temperature is sent down to the controller (Example: Xenta 121 controller). Below you can find out how to check the version number of the stat and how to perform the calibration.

There is not a way to upgrade older versions of the STR-150 to 1.4 or greater.

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Checking the STR-150 version number

The version number of the stat can be found as parameter P0.

1. View version:
   1. Push the fan and bypass button simultaneously for 2 seconds to display P0.
      
   2. The version number will be displayed here.

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Using the STR-150 Calibration Feature

1. Enter Configuration:
   1. Push the fan and bypass button simultaneously for 2 seconds to enter P0.
       
   2. In P0, hold down the bypass button and push the fan button three times to enter configuration mode.
      Note: the wrench symbol is lit when the STR-150 is in configuration mode.
       
2. In Configuration Mode:
   1. Press the fan button repeatedly until you reach parameter F0.
      Note: The two digits farthest to the left on the display show the parameter, while the two digits farthest to the right show the value.
       
   2. Use the increase or decrease button to adjust the value. The offset scale ranges from 0-99 which corresponds to -5.0 to +4.9 degrees. If the STR-150 is setup for degrees C, then the offset is exact. If the STR-150 is setup for degrees F, then the offset is recalculated to a corresponding value.
      
       
3. Exit Configuration Mode:
   1. Push the fan and bypass button simultaneously for 2 seconds or allow the idle timeout to exit configuration mode on its own.