McQuay MCS Fault Code E19

E19
Pumpdown failure
Warning
SAFETY WARNING: Commercial chillers contain high-pressure refrigerants and high-voltage electrical components (208V-4160V). Only EPA Section 608 certified technicians should perform diagnostic work. Always follow lockout/tagout procedures and wear appropriate PPE. Do not attempt repairs without proper training and equipment.
AI Summary

McQuay MCS Fault Code E19 is a warning alarm indicating: Pumpdown failure. The most common causes include Solenoid not closing. Estimated repair time: 1-2 hours. This alarm requires immediate attention by a certified HVAC technician.

Alarm Description

Pumpdown failure

Brand: McQuay  |  Model: MCS (Modular Chiller System)  |  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:

Quick Start: Check solenoid

Probable Causes

  • Solenoid not closing
  • Pressure not reaching setpoint
  • Timer expired
  • Non-condensables

Recommended Inspection Steps

  1. Check solenoid
  2. Verify pressure
  3. Inspect logic
  4. Vent non-condensables

Required Tools & Equipment

  • Digital multimeter
  • OEM service manual
  • Safety PPE (gloves, safety glasses)
  • 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 McQuay service representative for warranty-covered repairs

Related Fault Codes

Other McQuay MCS codes that may be related:

OEM Service Manual Reference

OEM Reference: McQuay MCS Modular Chiller Service Manual. Available through Daikin Applied technical support.

Frequently Asked Questions

What does McQuay MCS fault code E19 mean?

Fault code E19 on a McQuay MCS chiller indicates: Pumpdown failure. This is a warning alarm that requires diagnostic attention.

What causes McQuay MCS alarm code E19?

Common causes include: Solenoid not closing; Pressure not reaching setpoint; Timer expired

How do I fix McQuay MCS 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 McQuay service representative.

Disclaimer: All lookup data is for reference only. Do not use this information to replace certified professional HVAC technician judgment. Always refer to original OEM official service manual for McQuay MCS service procedures.