Lennox SCA Fault Code E06
Lennox SCA Fault Code E06 is a warning alarm indicating: Low pressure switch activated. The most common causes include Low refrigerant charge from leak. Estimated repair time: 2-4 hours (requires leak repair, evacuation, and refrigerant recharge). This alarm requires immediate attention by a certified HVAC technician.
Alarm Description
Low pressure switch activated
Brand: Lennox | Model: SCA (Air-Cooled Scroll Chiller) | Code: E06 | Severity: Warning
Observable Symptoms
- Suction pressure gauge reads below normal operating range
- Compressor may short cycle or run continuously without cooling
- Frost may appear on suction line or evaporator
What to Check First
Before diving into detailed diagnostics, start with this quick first check:
Probable Causes
- Low refrigerant charge from leak
- Expansion valve starving evaporator
- Evaporator water flow insufficient
- Fouled evaporator coils
Recommended Inspection Steps
- Check refrigerant subcooling and superheat
- Inspect expansion valve operation
- Measure evaporator water flow rate
- Check for refrigerant leaks
- Add refrigerant if charge is low
Required Tools & Equipment
- Coil cleaning brush and coil cleaner
- Electronic leak detector
- Oil level sight glass inspection tool
- PT chart for refrigerant type
- Safety PPE (gloves, safety glasses, face shield)
Estimated Repair Time
2-4 hours (requires leak repair, evacuation, and refrigerant recharge)
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 Lennox service representative for warranty-covered repairs
Related Fault Codes
Other Lennox SCA codes that may be related:
OEM Service Manual Reference
OEM Reference: Lennox SCA Air-Cooled Scroll Chiller Service Manual. Available through Lennox Commercial technical support.
Frequently Asked Questions
What does Lennox SCA fault code E06 mean?
Fault code E06 on a Lennox SCA chiller indicates: Low pressure switch activated. This is a warning alarm that requires diagnostic attention.
What causes Lennox SCA alarm code E06?
Common causes include: Low refrigerant charge from leak; Expansion valve starving evaporator; Evaporator water flow insufficient
How do I fix Lennox SCA error code E06?
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 Lennox service representative.