Applicable Systems
RTAC 200

Symptoms

The expansion valve reports a fault. The valve may not be controlling refrigerant flow correctly.

Possible Causes

  • Expansion valve stepper motor failure
  • Valve control board communication fault

Troubleshooting Steps

  1. Step 1: Check the valve wiring and connector
    Wiring and connector are secure
  2. Step 2: Test the valve motor operation with the controller diagnostic
    Motor does not respond or responds incorrectly

How to Reset

To reset: Replace the expansion valve or control board, then power-cycle.

Source: Trane HVAC Service Manual, Trane Inc.

Category: HVAC Residential