TM44 Air Conditioning Inspection — What’s Involved and Why It Matters

What Is a TM44 Air Conditioning Inspection?

A TM44 air conditioning inspection is a mandatory assessment of your commercial building’s cooling systems, required by law under the Energy Performance of Buildings Regulations 2012. If your premises contain air conditioning with an effective rated output exceeding 12kW, you must have it inspected by an accredited energy assessor at least once every five years. This applies regardless of whether you own or lease the building — the person controlling the system bears the responsibility.

The regulations stem from the European Energy Performance of Buildings Directive (EPBD), which the UK retained post-Brexit. Their purpose is straightforward: to reduce energy waste in commercial cooling systems and cut carbon emissions across the built environment. A properly conducted inspection identifies inefficiencies, highlights maintenance issues, and provides actionable recommendations to improve your system’s performance.

AirCert provides TM44 inspection services across the North East and Yorkshire. Tom holds both Level 3 and Level 4 accreditation through Elmhurst Energy, the UK’s leading energy assessor accreditation body. This dual qualification allows assessment of everything from single split systems to complex multi-zone variable refrigerant flow installations.

Who Needs a TM44 Air Conditioning Inspection?

The 12kW effective rated output threshold determines whether your system falls within scope. This covers the combined cooling capacity of interconnected units, not individual components assessed separately. Many building managers assume their systems fall below the threshold, only to discover that aggregated capacity across multiple indoor units brings them firmly into scope.

Systems requiring inspection include:

• Split systems and multi-split configurations
• Variable refrigerant flow (VRF) and variable refrigerant volume (VRV) systems
• Chilled water systems with fan coil units
• Packaged rooftop units
• Centralised air handling units with cooling coils
• Close control units in server rooms and data centres

These regulations apply to offices, retail premises, hotels, restaurants, warehouses, factories, schools, universities, NHS trusts, leisure centres, and any other commercial or public building. All fuel types are covered — electric, gas absorption, and heat pump systems alike.

Domestic properties remain exempt, as do commercial systems with an effective rated output below 12kW. However, if you operate multiple smaller units that together exceed the threshold when serving the same building, you still require an inspection.

TM44 Inspection vs Routine Maintenance — A Critical Difference

One of the most common misconceptions involves confusing TM44 air conditioning inspections with standard servicing contracts. These are entirely separate activities with different purposes, carried out by different specialists.

Routine maintenance focuses on keeping equipment running — cleaning filters, checking refrigerant levels, testing electrical components, and replacing worn parts. Your maintenance contractor handles this work, typically on quarterly or annual schedules.

A TM44 inspection assesses energy efficiency and regulatory compliance. It examines whether your system is appropriately sized for the building’s cooling load, whether controls operate effectively, whether the installation meets current standards, and whether opportunities exist to reduce energy consumption. Only accredited energy assessors can conduct these inspections and issue valid certificates.

Having a current maintenance contract does not satisfy the legal requirement. You need both: regular servicing to maintain equipment reliability, and a TM44 inspection every five years to demonstrate EPBD compliance.

What Does the TM44 Inspection Process Involve?

The inspection follows a structured methodology defined in CIBSE TM44 guidance. On the day, Tom will assess every component affecting system efficiency, from outdoor condensers to indoor distribution units and the controls linking them together.

Equipment and Physical Assessment

The inspection covers all accessible components:

• Outdoor units — condensers, compressors, refrigerant pipework connections, condition of heat exchange surfaces, evidence of refrigerant leaks
• Indoor units — evaporators, fan coil units, air handling components, filters, ductwork connections, diffuser positions
• Refrigeration circuits — pipe insulation, joint integrity, signs of deterioration or damage
• Electrical connections — supply arrangements, isolation provision, cable condition
• Controls and timers — programmable settings, zone controls, sensor positions, thermostat calibration, building management system integration

Documentation Review

Records provide crucial context for understanding system performance over time. The inspection includes review of:

• Maintenance logs and service history
• Original commissioning records
• System manuals and technical specifications
• Previous TM44 reports and recommendations
• Any modifications or additions since installation

System Sizing Assessment

A key element involves evaluating whether the installed cooling capacity matches the building’s actual requirements. Oversized systems waste energy through short cycling and excessive part-load operation. Undersized systems run continuously without achieving comfort conditions. Either scenario indicates potential for improvement.

This assessment considers building orientation, glazing ratios, occupancy patterns, internal heat gains from equipment and lighting, and any changes to the building’s use since the system was installed.

Preparing for Your Inspection

Proper preparation ensures the inspection proceeds efficiently and produces the most useful recommendations. Before the visit, gather the following:

1. Maintenance records from your servicing contractor for the past five years
2. Original commissioning documentation if available
3. System manuals and equipment specifications
4. Previous TM44 inspection reports and certificates
5. Building floor plans showing equipment locations
6. Details of any system modifications or extensions

Arrange safe access to all equipment. This includes rooftop units, plant rooms, ceiling voids where indoor units are mounted, and any remote locations serving different building zones. If scaffold or specialist access equipment is required for rooftop condensers, organise this in advance.

Ensure someone with operational knowledge of the building remains available during the inspection. Questions about usage patterns, comfort complaints, and system behaviour help contextualise the technical findings.

Inspection Duration and Timescales

For straightforward sites with a single system — perhaps a typical office with one VRF installation — expect the inspection to take between one and two hours. This includes time for equipment assessment, documentation review, and preliminary discussion of findings.

Complex buildings with multiple systems require proportionally longer. A large retail unit with separate systems serving sales floor, stockroom, and offices might need three to four hours. Healthcare facilities, hotels, or multi-tenanted buildings with numerous independent systems could require a full day or more.

Following the site visit, Tom prepares the formal report and certificate. For most inspections, you will receive these within five working days. Complex sites with extensive recommendations may take slightly longer to ensure thoroughness and accuracy.

The TM44 Report and Certificate

The inspection produces two documents. The TM44 Advisory Report contains detailed findings, efficiency ratings, and prioritised recommendations for improvement. This is your working document — use it to plan maintenance, justify capital expenditure on upgrades, and demonstrate due diligence to auditors or prospective tenants.

The TM44 Inspection Certificate provides formal evidence of compliance. This document includes the building address, system details, inspection date, assessor credentials, and certificate reference number. Keep this accessible — enforcement officers can request it, and landlords must provide copies to tenants upon request.

Recommendations within the report are categorised by payback period and implementation complexity. Some improvements — optimising timer settings, adjusting temperature setpoints, improving controls — cost nothing or very little. Others, such as replacing aged equipment or adding zone controls, require capital investment but deliver substantial ongoing savings.

Case Study: Multi-Floor Teesside Office Building

A recent TM44 inspection for a four-storey office complex in Teesside illustrates what the process involves in practice. The building contained a 56kW VRF system with 24 indoor units across three floors, plus a separate 18kW split system serving the server room.

The inspection began with a detailed assessment of the rooftop condensing units. One of the two VRF outdoor units showed significant coil fouling from nearby ventilation exhaust, reducing heat rejection efficiency. The refrigerant pipework, installed externally down the building facade, had degraded insulation exposing sections to weather damage.

Internal assessment revealed three ceiling cassette units with blocked filters restricting airflow. Zone controls operated inconsistently — several areas ran cooling simultaneously with perimeter heating, wasting energy through conflicting operation. The server room system ran continuously at full capacity despite actual loads varying substantially throughout the day.

Documentation review showed regular maintenance visits, but service records lacked detail about efficiency-related checks. No evidence existed of controls optimisation since original commissioning eight years earlier.

The report contained twelve recommendations prioritised by cost-effectiveness. Immediate actions — cleaning the fouled condenser coil, replacing degraded insulation, servicing blocked filters — required minimal expenditure but would recover costs within months through reduced energy consumption. Medium-term recommendations addressed controls integration and temperature setpoint optimisation. Longer-term suggestions included variable speed drives for the server room system and enhanced zone controls for the open-plan office floors.

The facilities manager used the report to secure budget approval for the immediate works and plan phased implementation of remaining recommendations over the following eighteen months.

Book Your TM44 Air Conditioning Inspection

Whether you manage a single office or multiple commercial properties across the North East and Yorkshire, AirCert provides thorough, professional TM44 inspection services with clear reporting and practical recommendations. Tom’s dual accreditation ensures expertise across all system types, from simple splits to complex VRF installations.

If your five-year inspection is due, or you are uncertain whether your systems require assessment, get in touch for straightforward advice and competitive pricing. [INTERNAL LINK: get-a-quote] Complete the online form or call directly to discuss your requirements.

[META: TM44 air conditioning inspection services for commercial buildings across the North East and Yorkshire. Accredited assessor, clear reports, practical recommendations.]