For qualifying England and Wales systems, the TM44 threshold concerns effective rated cooling output of more than 12 kW and applicable rules for grouped systems under common operational control. The correct answer requires actual system data rather than adding every electrical rating or assuming all separately occupied spaces belong to one installation.
What you need to know
- Identify cooling plant across the whole relevant building, not only visible room units.
- Distinguish genuine effective rated cooling output from electrical input and heating output.
- Review grouped units under common control without double-counting a multi-split system.
- Mark uncertain capacity or responsibility UNKNOWN until evidence is available.
Why building inventories miss air-conditioning systems
A facilities team may know about main office cooling yet overlook tenant-installed units, systems serving server rooms, rooftop condensers or later fit-out equipment. Missing plant records can make an initial quotation unreliable and leave an existing inspection report's coverage unclear.
Walk the documented equipment schedule with a competent site contact. The objective is to map real installed systems and controls, not infer capacity from floor area, occupancy or an EPC rating.
What information helps a quotation?How the more-than-12-kW rule is assessed
The England and Wales framework generally applies where effective rated output exceeds 12 kW, and certain smaller cooling units under the same relevant person's control may be considered together. A unit rated at exactly 12 kW is not automatically above that threshold solely because of rounding.
Cooling capacity is not the same as electrical power input or a heat pump's heating-mode output. Ask for manufacturer technical data where the label is ambiguous.
Read the TM44 inspection thresholdAvoid double-counting split and VRF systems
An indoor head and its outdoor plant are not necessarily two independent cooling capacities to be added together. Multi-split and variable-refrigerant systems should be assessed using their actual engineering configuration and effective rated output.
Recording individual components remains helpful, but the compliance calculation needs to reflect the system rather than sum every number in the plant register. An accredited assessor can clarify the assessment boundary.
Use the capacity screening guideLandlord-controlled and tenant-controlled units
Different occupiers can operate different cooling systems in the same building. Establish control of the plant and temperature settings, the responsibility arrangements and whether the previous inspection reports cover independently installed equipment.
A landlord's general report should not silently be treated as covering equipment that a tenant installed later. Equally, one shared postcode does not prove all equipment has a common responsible person.
Review responsibility for separate systemsWhat to do when the asset list is incomplete
Start with the location, approximate equipment type, available photographs of nameplates where safe, model references, and the site's maintenance contractor. Record unknown equipment facts rather than inventing a capacity or an inspection date.
An initial review can establish the questions needed for formal scoping. A website checklist is not a government compliance determination or a substitute for an appropriately accredited energy assessor.
Build a usable estate evidence registerNext steps when qualifying systems are identified
Check the latest TM44 inspection report for the actual building and plant, identify the responsible person and determine the correct inspection timetable. In England and Wales, qualifying inspections have a maximum five-year periodic interval.
For a potential inspection, send the building address, plant information and access details. The quotation should identify accredited-assessor scope, reporting and applicable lodgement without assuming equipment repairs or F-Gas checks are included.
Request a correctly scoped TM44 quotationCheck the governing guidance
This article does not authenticate a government register entry or establish the status of an individual building. Confirm the applicable national framework and the actual installed equipment before relying on a compliance conclusion.
England and Wales legal points are anchored in current government publications and the regulations. Technical applicability for a specific building still requires its actual system information.