York YCAL Fault Code H4
York YCAL Fault Code H4 is a warning alarm indicating: Motor winding temperature high. The most common causes include Motor bearing wear. Estimated repair time: 1-2 hours. This alarm requires immediate attention by a certified HVAC technician.
Alarm Description
Motor winding temperature high
Brand: York | Model: YCAL (Air-Cooled Scroll Chiller) | Code: H4 | 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:
Probable Causes
- Motor bearing wear
- High load condition
- Inadequate motor cooling
- Voltage imbalance
Recommended Inspection Steps
- Measure motor winding temperature
- Check motor current balance
- Inspect motor bearings
- Verify motor cooling
Required Tools & Equipment
- Clamp-on ammeter
- Digital multimeter
- Infrared thermometer or calibrated temperature probe
- 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 YCAL codes that may be related:
OEM Service Manual Reference
OEM Reference: York YCAL Air-Cooled Scroll Chiller Installation and Maintenance Manual (Form 160.00-S1). Johnson Controls/York Technical Literature.
Frequently Asked Questions
What does York YCAL fault code H4 mean?
Fault code H4 on a York YCAL chiller indicates: Motor winding temperature high. This is a warning alarm that requires diagnostic attention.
What causes York YCAL alarm code H4?
Common causes include: Motor bearing wear; High load condition; Inadequate motor cooling
How do I fix York YCAL error code H4?
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.