York YVAA Fault Code U10

U10
Low refrigerant level alarm
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

York YVAA Fault Code U10 is a warning alarm indicating: Low refrigerant level alarm. The most common causes include Refrigerant leak detected. Estimated repair time: 1-2 hours. This alarm requires immediate attention by a certified HVAC technician.

Alarm Description

Low refrigerant level alarm

Brand: York  |  Model: YVAA (Variable Speed Screw Chiller)  |  Code: U10  |  Severity: Warning

Observable Symptoms

  • Controller displays alarm code and description
  • Chiller may be locked out or running in degraded mode
  • Alarm indicator light is illuminated on control panel

What to Check First

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

Quick Start: Check subcooling

Probable Causes

  • Refrigerant leak detected
  • Subcooling below threshold
  • Level sensor indicating low charge

Recommended Inspection Steps

  1. Check subcooling
  2. Perform leak test
  3. Repair and recharge
  4. Verify by weigh-in

Required Tools & Equipment

  • EPA-certified refrigerant recovery unit
  • Electronic leak detector
  • PT chart for refrigerant type
  • Safety PPE (gloves, safety glasses, face shield)

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 York service representative for warranty-covered repairs

Related Fault Codes

Other York YVAA codes that may be related:

OEM Service Manual Reference

OEM Reference: York YVAA Variable Speed Screw Chiller Service Manual (Form 160.72-S1). Johnson Controls Technical Literature.

Frequently Asked Questions

What does York YVAA fault code U10 mean?

Fault code U10 on a York YVAA chiller indicates: Low refrigerant level alarm. This is a warning alarm that requires diagnostic attention.

What causes York YVAA alarm code U10?

Common causes include: Refrigerant leak detected; Subcooling below threshold; Level sensor indicating low charge

How do I fix York YVAA error code U10?

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 York 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 York YVAA service procedures.