McQuay PFS Fault Code E27
McQuay PFS Fault Code E27 is a warning alarm indicating: Remote start/stop fault. The most common causes include Remote start/stop signal not received. Estimated repair time: 1-2 hours. This alarm requires immediate attention by a certified HVAC technician.
Alarm Description
Remote start/stop fault
Brand: McQuay | Model: PFS (Air-Cooled Scroll Chiller) | Code: E27 | 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
- Remote start/stop signal not received
- Remote wiring damaged
- BAS communication issue
Recommended Inspection Steps
- Check remote start/stop wiring
- Verify BAS signal
- Test remote start/stop circuit
- Repair wiring or replace remote panel
Required Tools & Equipment
- EPA-certified refrigerant recovery unit
- Safety PPE (gloves, safety glasses, face shield)
- Wire tracing and continuity tester
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 McQuay service representative for warranty-covered repairs
Related Fault Codes
Other McQuay PFS codes that may be related:
OEM Service Manual Reference
OEM Reference: McQuay PFS Air-Cooled Scroll Chiller Service Manual. Available through Daikin Applied (formerly McQuay) technical support.
Frequently Asked Questions
What does McQuay PFS fault code E27 mean?
Fault code E27 on a McQuay PFS chiller indicates: Remote start/stop fault. This is a warning alarm that requires diagnostic attention.
What causes McQuay PFS alarm code E27?
Common causes include: Remote start/stop signal not received; Remote wiring damaged; BAS communication issue
How do I fix McQuay PFS error code E27?
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 McQuay service representative.