Air Inspections

What Is a TM44 Inspection (and Why You Need One)

optimA1radmin25 — Wed, 24 Sep 2025 11:32:29 +0000

What Is a TM44 Inspection (and Why You Need One)

A TM44 inspection, also known as an Air Conditioning Energy Assessment (ACEA), is a legally required evaluation of commercial air conditioning systems in the UK. If your system’s output exceeds 12 kW (or multiple units combined do), you must arrange a TM44 inspection every five years.

While compliance is non-negotiable, a good TM44 can also reveal energy savings, improve performance, and reduce carbon emissions — making it more than just a regulatory burden.

What Does “TM44” Mean & Where It Comes From

The term “TM44” originates from a Technical Memorandum (TM44) published by CIBSE (the Chartered Institution of Building Services Engineers), which sets out guidelines and best practice for air conditioning inspections.

These inspections were introduced under the Energy Performance of Buildings (Certificates & Inspections) Regulations, which implement the European Energy Performance of Buildings Directive (EPBD) in UK law.

Who Needs a TM44 Inspection?

You need a TM44 inspection if:

Your air conditioning system has an effective rated output above 12 kW (cooling).
Multiple smaller units controlled by the same person add up to more than 12 kW.
You manage or control the HVAC systems (as building owner, facilities manager, or landlord).

If your system is below 12 kW or all units combined are below that threshold, a TM44 inspection is not required under the regulation.

What Happens During a TM44 Inspection?

A TM44 inspection involves the following steps:

Data gathering & site review — The assessor collects system details: age, capacity, configuration, control type, previous maintenance records.
Visual inspection — All major components are inspected: outdoor units, indoor units, ducting, controls, filters, refrigerant circuits. Faults, leakage, wear and inefficiencies are identified.
Performance comparison — The assessor compares installed capacity vs actual building cooling demand, and checks if controls are optimised for energy efficiency.
Recommendations report — You receive a detailed TM44 report and certificate, which includes:
- System performance and inefficiencies
- Faults and repairs needed
- Control & operational improvements
- Suggestions for upgrades or replacement if necessary
- Certificate lodged on the government register
  
  Note: There’s no legal duty to implement all recommendations — but many of them offer real savings and performance gains.

How Often & What Happens If You Don’t Comply

Frequency: TM44 inspections must be carried out at least every five years.
First inspection dates: Systems installed after 1 January 2008 must have their first TM44 within five years of use.
Legal consequences: If an inspection is overdue or missing, local authorities can impose a £300 fine per system or building.
Further fine: You may also be fined £200 if you fail to provide the outstanding inspection report within 7 days of a request.

Why It Matters (Beyond Compliance)

A TM44 inspection is not just a legal tick-box — it’s a tool to optimise your building’s performance:

Energy savings & cost reduction — Uncover control inefficiencies, leakage, poor scheduling — many offer low-cost fixes.
Carbon & sustainability gains — More efficient operation helps reduce your emissions footprint.
Improved lifespan & reliability — Identifying faults early helps prevent breakdowns and extends system life.
Informed decision-making — The report gives you clear data to decide whether to upgrade, replace, or optimise controls.

Next Steps & What You Should Do Now

Check your HVAC installation documents — find the rated output, age, and service history
Check the Landmark Register — see if there’s an existing TM44 certificate lodged for your property
Contact an accredited assessor (Level 3 or Level 4) to arrange an inspection
Review the report carefully when you get it, and consider implementing low-cost improvements or scheduling bigger upgrades

Let's talk

How can we help you?

From TM44 compliance to identifying potential energy savings, we provide expert support to keep your air-conditioning system efficient and fully compliant.

Email address

tm44@airinspections.co.uk

General enquiries

01335 342445

Headquarters

Optimair Limited, 19 St Christopher's Way, Pride Park, Derby, DE24 8JY

Level 3 vs Level 4 TM44 Inspections — What’s the Difference?

optimA1radmin25 — Wed, 24 Sep 2025 11:27:36 +0000

Level 3 vs Level 4 TM44 Inspections — What’s the Difference?

Choosing the right level of TM44 inspection is essential to ensure compliance and get meaningful insights from your assessment.
In this article, we’ll explain the difference between Level 3 and Level 4 inspections, when each is required, and how that impacts cost, complexity, and the value you’ll receive.

What Are Level 3 and Level 4 Inspections?

Level 3 inspections are tailored to simpler systems — for example, split systems, VRF (Variable Refrigerant Flow) units, or other packaged cooling systems without centralised plant.

Level 4 inspections are for complex systems involving centralised plant like air handling units (AHUs), central chillers, and multiple terminal units — systems that are more integrated and have multiple control zones.

When Is Each Level Required?

Type of System	Typical Scenario	Which Level
Split units, VRF systems, packaged cooling systems	Multiple small units in individual rooms or offices	Level 3
Systems with central chillers, AHUs, ducted air distribution, multiple zones	Large office blocks, shopping centres, multi-zone commercial buildings	Level 4

Key Differences: Scope, Sampling & Complexity

1. Scope & Components Inspected

Level 3 will focus on the major units and typical controls associated with those units (compressors, indoor units, filters, basic controls)
Level 4 must inspect central plant, ductwork, control systems across zones, mixing boxes, and sometimes partial sampling of terminal units and AHUs.

2. Sampling Requirements

Because inspecting every single component in a large system is impractical, Level 4 often uses sampling (e.g. a percentage of AHUs or terminal units) to conclude the system.

3. Time, Effort & Cost

Level 4 inspections take longer, require more data collection, more complex analysis, and larger reports — so the cost is higher.

4. Report Complexity & Recommendations

Because Level 4 systems are more integrated, the recommendations may include advanced control strategies, zone scheduling, optimization between plant and terminal systems — not just “fix this filter / loosen this setting.”

Why It Matters to You

Compliance Risk: Using the incorrect level may lead to an invalid report or enforcement action.
Cost Efficiency: You don’t want to overpay by doing a Level 4 when Level 3 is appropriate — but underestimating complexity can lead to missing crucial issues.
Actionable Recommendations: A properly scoped inspection delivers insights that match the complexity of your system — so the advice is realistic and relevant.

How to Know Which Level You Need

Review your system design — Are you running central chillers / AHUs / duct networks?
Check ventilation & zoning — Are there multiple zones served by a central plant?
Consult a knowledgeable assessor — A qualified inspector can make the final determination based on your system and site conditions.

Next Steps & What to Do Now

Gather your system documentation — model, capacity, layout, control drawings
Contact an accredited assessor and describe your system — ask whether it likely fits Level 3 or 4
Be prepared to provide access and system history so the assessor can scope the inspection properly

Let's talk

How can we help you?

From TM44 compliance to identifying potential energy savings, we provide expert support to keep your air-conditioning system efficient and fully compliant.

Email address

tm44@airinspections.co.uk

General enquiries

01335 342445

Headquarters

Optimair Limited, 19 St Christopher's Way, Pride Park, Derby, DE24 8JY

How a TM44 Inspection Can Save You Money & Cut Carbon

optimA1radmin25 — Wed, 24 Sep 2025 11:04:23 +0000

How a TM44 Inspection Can Save You Money & Cut Carbon

A TM44 inspection is a legal requirement for any building in the UK with air conditioning systems above 12 kW, but it can also be one of the most valuable tools for reducing operating costs and improving energy performance.
Beyond compliance, a well-conducted TM44 assessment highlights how efficiently your systems are running — and where savings can be made.

Where TM44 Inspections Deliver Value

During a TM44 inspection, the assessor evaluates how each part of your cooling system operates: controls, sizing, maintenance, and energy use.
In doing so, they often uncover simple inefficiencies that cost hundreds or even thousands of pounds a year in wasted energy.
These might include systems left running when areas are unoccupied, poor thermostat placement, blocked filters, or oversized units working far below capacity.

Correcting these issues usually requires low-cost changes such as adjusting control schedules, recalibrating thermostats, or improving airflow.
In larger or older systems, recommendations may include upgrading to variable-speed drives, improved zoning, or higher-efficiency components.
Each improvement not only cuts energy use but can also extend equipment life and improve comfort for building occupants.

The Link Between Efficiency and Carbon Reduction

Because air conditioning can account for a significant portion of a building’s energy consumption, every kilowatt saved has a measurable impact on emissions.
A TM44 report includes guidance on how to reduce this load, helping you support your organisation’s carbon reduction plan or sustainability goals.
Simple operational improvements can reduce energy use by 10–20%, while targeted upgrades can go even further — lowering both carbon output and running costs over the long term.

Turning Compliance into Opportunity

Many businesses treat TM44 inspections as a box-ticking exercise, but those who act on the findings often see quick returns.
By combining the legal requirement with proactive energy management, you turn a routine assessment into a meaningful performance review.
That means fewer unexpected breakdowns, lower maintenance costs, and tangible progress toward environmental targets — all while staying fully compliant.

Maximising Value from Every Inspection

At Air Inspections, we believe compliance should create value, not complexity.
Our accredited assessors deliver clear, practical advice that helps you cut costs, improve system reliability, and reduce your environmental footprint — making every TM44 inspection a genuine investment in efficiency.

Let's talk

How can we help you?

From TM44 compliance to identifying potential energy savings, we provide expert support to keep your air-conditioning system efficient and fully compliant.

Email address

tm44@airinspections.co.uk

General enquiries

01335 342445

Headquarters

Optimair Limited, 19 St Christopher's Way, Pride Park, Derby, DE24 8JY

TM44 Air Conditioning Inspections for Costco UK

optimA1radmin25 — Wed, 24 Sep 2025 10:39:04 +0000

Costco

Project Overview

Air Inspections carried out nationwide TM44 inspections across over 30 Costco UK locations. Each site required detailed assessments of air conditioning and ventilation systems to ensure compliance with the Energy Performance of Buildings Regulations (EPBD).

Our Role

Our accredited inspectors evaluated system performance, control efficiency, and maintenance standards for a mix of retail and warehouse environments.
Through a consistent process, we identified opportunities for improved energy use and operational efficiency while ensuring all certificates were lodged with the Government’s Landmark Registry.

Outcome

The project ensured full TM44 compliance across the retailer’s UK portfolio and provided Costco with actionable insights into system efficiency. The results supported lower operational costs and a stronger approach to sustainability across multiple high-traffic locations.

Let's talk

How can we Help?

From TM44 compliance to identifying potential energy savings, we provide expert support to keep your air-conditioning system efficient and fully compliant.

Email address

tm44@airinspections.co.uk

General enquiries

01335 342445

Headquarters

Optimair Limited, 19 St Christopher's Way, Pride Park, Derby, DE24 8JY

Nationwide TM44 Inspections for Leonardo Hotels

optimA1radmin25 — Wed, 24 Sep 2025 10:36:59 +0000

Leonardo Hotels

Project Overview

Air Inspections completed a nationwide programme of TM44 inspections across more than 30 Leonardo Hotels across the UK. Each site required a detailed review of air conditioning and ventilation systems to maintain compliance with the Energy Performance of Buildings Regulations (EPBD).

Our Role

Our accredited assessors carried out professional inspections across hotel environments of varying scale and design.
Each assessment focused on energy efficiency, control optimisation, and maintenance standards — ensuring systems operated reliably and in line with TM44 requirements.

Outcome

The project achieved full TM44 compliance for all hotel sites, with detailed reports highlighting energy-saving opportunities and practical steps to improve system performance. The work supported Leonardo Hotels’ ongoing commitment to sustainability and efficient operation across their national portfolio.

Let's talk

How can we Help?

From TM44 compliance to identifying potential energy savings, we provide expert support to keep your air-conditioning system efficient and fully compliant.

Email address

tm44@airinspections.co.uk

General enquiries

01335 342445

Headquarters

Optimair Limited, 19 St Christopher's Way, Pride Park, Derby, DE24 8JY

TM44 Compliance Surveys for Big Yellow Self Storage

optimA1radmin25 — Tue, 23 Sep 2025 23:00:54 +0000

Big Yellow Self Storage

Project Overview

Air Inspections conducted comprehensive TM44 air conditioning and ventilation inspections across more than 30 Big Yellow Self Storage sites throughout the UK. Each location required full assessment to ensure compliance with the Energy Performance of Buildings Regulations (EPBD).

Our Role

Our accredited assessors inspected a range of HVAC systems used within storage facilities, focusing on energy performance, control settings, and system condition.
The surveys were completed efficiently across multiple sites, ensuring all reports met government standards and were lodged with the Landmark Registry.

Outcome

The project achieved full TM44 compliance across Big Yellow’s UK portfolio. The inspection findings provided valuable insight into system operation and identified practical opportunities for improved efficiency and long-term reliability across the company’s facilities.

Let's talk

How can we Help?

From TM44 compliance to identifying potential energy savings, we provide expert support to keep your air-conditioning system efficient and fully compliant.

Email address

tm44@airinspections.co.uk

General enquiries

01335 342445

Headquarters

Optimair Limited, 19 St Christopher's Way, Pride Park, Derby, DE24 8JY