Daikin AGZ Fault Code E19
Daikin AGZ Fault Code E19 is a warning alarm indicating: Expansion valve driver fault. The most common causes include Expansion valve driver board failure. Estimated repair time: 1-3 hours (requires board replacement, configuration, and commissioning). This alarm requires immediate attention by a certified HVAC technician.
Alarm Description
Expansion valve driver fault
Brand: Daikin | Model: AGZ (Modular Scroll Chiller) | Code: E19 | 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
- Expansion valve driver board failure
- Driver communication lost
- Valve motor short circuit
Recommended Inspection Steps
- Check driver board power supply
- Verify communication to driver
- Test valve motor resistance
- Replace driver board or valve motor
Required Tools & Equipment
- Digital multimeter
- Safety PPE (gloves, safety glasses, face shield)
Estimated Repair Time
1-3 hours (requires board replacement, configuration, and commissioning)
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 Daikin service representative for warranty-covered repairs
Related Fault Codes
Other Daikin AGZ codes that may be related:
OEM Service Manual Reference
OEM Reference: Daikin AGZ Modular Scroll Chiller Service Manual. Available through Daikin Applied technical support.
Frequently Asked Questions
What does Daikin AGZ fault code E19 mean?
Fault code E19 on a Daikin AGZ chiller indicates: Expansion valve driver fault. This is a warning alarm that requires diagnostic attention.
What causes Daikin AGZ alarm code E19?
Common causes include: Expansion valve driver board failure; Driver communication lost; Valve motor short circuit
How do I fix Daikin AGZ error code E19?
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 Daikin service representative.