Daikin AGZ Fault Code E18
Daikin AGZ Fault Code E18 is a warning alarm indicating: Compressor contactor fault. The most common causes include Contactor coil failure. Estimated repair time: 1-2 hours. This alarm requires immediate attention by a certified HVAC technician.
Alarm Description
Compressor contactor fault
Brand: Daikin | Model: AGZ (Modular Scroll Chiller) | Code: E18 | 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
- Contactor coil failure
- Contactor contacts welded or pitted
- Mechanical binding of contactor
Recommended Inspection Steps
- Check contactor coil voltage
- Inspect contactor contacts for pitting or welding
- Manually test contactor operation
- Replace contactor if contacts are damaged
Required Tools & Equipment
- Coil cleaning brush and coil cleaner
- Digital multimeter
- Oil level sight glass inspection tool
- 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 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 E18 mean?
Fault code E18 on a Daikin AGZ chiller indicates: Compressor contactor fault. This is a warning alarm that requires diagnostic attention.
What causes Daikin AGZ alarm code E18?
Common causes include: Contactor coil failure; Contactor contacts welded or pitted; Mechanical binding of contactor
How do I fix Daikin AGZ error code E18?
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.