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Free Engineering Tool

Chiller Diagnostic & Refrigerant Calculator

Calculate superheat and subcool for the common chiller refrigerants, then walk through a structured diagnostic for the fault categories chillers actually trip on. Free, no signup.

R410A: Most common in commercial AC and small-to-mid air-cooled chillers installed 2005–2024

Phasing out under EU/UK F-Gas — restricted in new equipment from 2025/2027

Suction side (for superheat)

Liquid side (for subcool — optional)

Results

Superheat6.4 KIn range

Evaporating at 5.6°C • target 5.0 K–8.0 K

Superheat is within the manufacturer's target band. Expansion valve and refrigerant charge look healthy on the suction side.

Subcool6.3 KIn range

Condensing at 46.3°C • target 4.0 K–8.0 K

Subcool is within the manufacturer's target band. Refrigerant charge and condenser performance look healthy on the discharge side.

Calculations use approximate saturation curves accurate to within ~1°C across the normal HVAC operating range. Always cross-reference with the manufacturer's PT chart before charging or commissioning decisions.

F-Gas safety reminder

All refrigerant work in the UK and EU must be carried out by F-Gas certified engineers under the F-Gas Regulation. This tool provides general diagnostic guidance — it does not authorise refrigerant handling or electrical work on chillers. Always cross-reference manufacturer service literature.

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Frequently asked questions

Search your own chiller O&M manuals with AI

Manufacturer-specific fault codes, setpoints, and torque values live inside the OEM O&M manual. Upload them to PM Assist and search in plain English with source-cited answers.

  • AI search across all your chiller and HVAC documentation
  • Source-cited answers from the original manuals
  • Per-building document organisation
  • Team collaboration and access control
  • No credit card required to start