Carrier 30XA Fault Code 2

2
Evaporator leaving fluid thermistor failure
Warning
SAFETY WARNING: Commercial chillers contain high-pressure refrigerants and high-voltage electrical components (208V-4160V). Only EPA Section 608 certified technicians should perform diagnostic work. Always follow lockout/tagout procedures and wear appropriate PPE. Do not attempt repairs without proper training and equipment.
AI Summary

Carrier 30XA Fault Code 2 is a warning alarm indicating: Evaporator leaving fluid thermistor failure. The most common causes include Thermistor element degraded or failed. Estimated repair time: 1-2 hours. This alarm requires immediate attention by a certified HVAC technician.

Alarm Description

Evaporator leaving fluid thermistor failure

Brand: Carrier  |  Model: 30XA (Screw Compressor Chiller)  |  Code: 2  |  Severity: Warning

Observable Symptoms

  • Temperature reading on controller display shows abnormal value or dashes
  • Chiller may not start or cycles erratically due to incorrect temperature input

What to Check First

Before diving into detailed diagnostics, start with this quick first check:

Quick Start: Disconnect thermistor and measure resistance at known temperature

Probable Causes

  • Thermistor element degraded or failed
  • Connector corrosion or loose connection
  • Control board analog input circuit damaged

Recommended Inspection Steps

  1. Disconnect thermistor and measure resistance at known temperature
  2. Inspect connector pins for corrosion or bent contacts
  3. Compare readings with entering fluid thermistor for cross-reference
  4. Replace thermistor assembly if faulty

Required Tools & Equipment

  • Digital multimeter
  • Infrared thermometer or calibrated temperature probe
  • Safety PPE (gloves, safety glasses, face shield)
  • Wire tracing and continuity tester

Estimated Repair Time

1-2 hours

When to Call a Professional

  • If the fault persists after completing all recommended inspection steps
  • If you observe unusual noises, vibrations, or oil leaks from the compressor
  • If refrigerant charge levels are outside OEM specifications and EPA-certified recovery is needed
  • If electrical measurements show voltage imbalance greater than 2% between phases
  • If the fault recurs immediately after reset, indicating an unresolved safety condition
  • Contact an authorized Carrier service representative for warranty-covered repairs

Related Fault Codes

Other Carrier 30XA codes that may be related:

OEM Service Manual Reference

OEM Reference: Carrier 30XA Service Manual (Form 30XA-6SI). Available through Carrier Commercial Systems technical support or partnered distributors.

Frequently Asked Questions

What does Carrier 30XA fault code 2 mean?

Fault code 2 on a Carrier 30XA chiller indicates: Evaporator leaving fluid thermistor failure. This is a warning alarm that requires diagnostic attention.

What causes Carrier 30XA alarm code 2?

Common causes include: Thermistor element degraded or failed; Connector corrosion or loose connection; Control board analog input circuit damaged

How do I fix Carrier 30XA error code 2?

Follow the recommended inspection steps below. Start with the quick check, then proceed through each step. If the fault persists after all steps, contact an authorized Carrier service representative.

Disclaimer: All lookup data is for reference only. Do not use this information to replace certified professional HVAC technician judgment. Always refer to original OEM official service manual for Carrier 30XA service procedures.