In England and Wales, the Energy Performance of Buildings framework requires regular inspection of air-conditioning systems with an effective rated output of more than 12 kW. Inspections must be carried out by an accredited air-conditioning energy assessor at intervals not exceeding five years, with a written report kept by the relevant person. CIBSE TM44 is the established methodology referenced in official guidance. This is an energy-efficiency inspection duty, separate from F-gas leak checks and from ordinary maintenance visits, though good records help all three.
What the EPBD-derived duty actually is
The European Energy Performance of Buildings Directive led UK administrations to require regular inspection of larger air-conditioning systems. In England and Wales the duty sits in the Energy Performance of Buildings Regulations: systems over 12 kW effective rated output need inspection by an energy assessor no less often than every five years.
Where one person controls several individual units in a building, those units are treated as one system for this purpose. Portfolio managers should not assume that a cluster of 3.5 kW wall splits escapes the threshold.
TM44 as the practical method
GOV.UK's inspection guide draws on CIBSE TM44 for how assessors should inspect packaged and central plant, review sizing against cooling need, and recommend improvements. The output is an inspection report with advice, not an automatic instruction to replace every unit.
Assessors typically need access to indoor and outdoor plant, controls, and maintenance records. Incomplete log books slow the visit and weaken the usefulness of the advice.
- Confirm whether combined cooling output exceeds 12 kW under one operator.
- Book an accredited air-conditioning energy assessor, not only a general electrician.
- Keep the lodged report with the building energy file.
- Diary the five-year renewal before expiry.
How compliance differs from servicing and F-gas
A filter clean or maintenance contract does not replace a TM44-style inspection. F-gas leak checks and company certification address refrigerant obligations, not the EPB inspection report. Commercial landlords and facilities managers often need all three strands documented.
When requesting installer or maintainer quotes through this site, say whether you need routine servicing, leak-check evidence, inspection support or a combination, so companies do not under-scope the brief.
Frequently asked questions
Is TM44 the legal name of the duty?
TM44 is the CIBSE methodology widely used to deliver the inspection. The legal duty in England and Wales comes from the Energy Performance of Buildings Regulations and related official guidance.
Does every shop with one wall unit need an inspection?
Not automatically. The 12 kW effective rated output threshold and how units are grouped under one operator decide the duty. Check the equipment schedule against current GOV.UK guidance.
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How this guide was prepared
This guide was written by the Local AC Installers Editorial Team. We compare official guidance, legislation and established consumer information, separate general information from project-specific advice, and show publication dates and sources. We do not accept installer accreditation claims at face value.