Daikin WME Fault Code H1

H1
High pressure switch
Critical
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

Daikin WME Fault Code H1 is a critical safety alarm indicating: High pressure switch. The most common causes include Discharge pressure too high. Estimated repair time: 45-90 minutes. This alarm requires immediate attention by a certified HVAC technician.

Alarm Description

High pressure switch

Brand: Daikin  |  Model: WME (Water-Cooled Screw Chiller)  |  Code: H1  |  Severity: Critical

Observable Symptoms

  • Compressor shuts down on high pressure safety cutout
  • Discharge pressure gauge reads above normal operating range
  • Condenser may feel hot to touch or airflow feels restricted

What to Check First

Before diving into detailed diagnostics, start with this quick first check:

Quick Start: Check condenser

Probable Causes

  • Discharge pressure too high
  • Condenser not rejecting heat
  • Non-condensables

Recommended Inspection Steps

  1. Check condenser
  2. Verify fan or water flow
  3. Vent non-condensables

Required Tools & Equipment

  • PT chart for refrigerant type
  • Refrigerant manifold gauge set
  • Safety PPE (gloves, safety glasses, face shield)

Estimated Repair Time

45-90 minutes

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 WME codes that may be related:

U0U1U2E0E1

OEM Service Manual Reference

OEM Reference: Daikin WME Water-Cooled Screw Chiller Service Manual. Available through Daikin Applied technical support.

Frequently Asked Questions

What does Daikin WME fault code H1 mean?

Fault code H1 on a Daikin WME chiller indicates: High pressure switch. This is a critical safety alarm that requires diagnostic attention.

What causes Daikin WME alarm code H1?

Common causes include: Discharge pressure too high; Condenser not rejecting heat; Non-condensables

How do I fix Daikin WME error code H1?

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.

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 Daikin WME service procedures.