TM44 inspections are one of the less familiar duties of running a building with air conditioning. Many offices, shops, restaurants and surgeries are covered without the people running them knowing. This guide explains what the law requires, using the GOV.UK guide to air conditioning inspections, and how we help you prepare and act on the findings.
One point up front: inspections must be carried out by an accredited energy assessor. AirCon Doctor is not an energy assessor. We arrange inspections, prepare systems for them and carry out the remedial and maintenance work the report recommends. This is general information, not legal advice.
The law and the name
The duty comes from the Energy Performance of Buildings (Certificates and Inspections) (England and Wales) Regulations 2012. “TM44” is the name of the CIBSE technical memorandum that sets out the inspection method, which is why most people call them TM44 inspections.
Which systems are covered: the 12 kW threshold
GOV.UK says the rules cover systems with an effective rated output of more than 12 kW. Crucially, that’s measured across the building, not unit by unit. One or more air conditioning units within a building controlled by a single person are treated as a single system, so several small split systems that are each well under 12 kW can add up to more than 12 kW together.
A typical example is a small office with four or five wall-mounted units. Each might be small, but the total can easily pass 12 kW. If you aren’t sure, list every unit’s cooling capacity from its rating plate or manual and add them up. We can do that for you on a service visit.
How often
GOV.UK says inspections must be no more than five years apart. If a building changes hands and there’s no report, the new person in control must have the system inspected within three months.
Who is responsible
The duty falls on the person who controls the operation of the system. That may be the building owner, a tenant, or a facilities or managing agent, depending on who controls the technical functioning of the air conditioning. They must make sure the inspection is done, keep the latest report and pass it on to anyone who takes over control.
Want it done properly? AirCon Doctor installs, repairs and services air conditioning and heat pumps across London and the South East, from our base in East Grinstead. We’re an F-Gas certified company and NICEIC approved. Get a fixed-price quote.
Who can inspect, and the register
Only an energy assessor who is a current member of an accreditation scheme can carry out the inspection. Since 6 April 2012, reports must be lodged on the Energy Performance of Buildings Register to be valid, and each gets a reference number. Ask for the reference when you receive the report.
Penalties
Enforcement is by local weights and measures authorities, usually Trading Standards. GOV.UK states that the penalty for not having a report is currently £300, and that failing to provide a report to a Trading Standards officer within seven days carries a fixed penalty of £200.
What the report covers
The report covers, at minimum, the likely efficiency of the system and suggestions for improvement. GOV.UK lists faults, maintenance, controls and system sizing, with a summary of key recommendations. Typical findings include:
- dirty filters and coils reducing efficiency;
- controls set so heating and cooling can run at the same time;
- timers that don’t match occupancy;
- systems oversized or undersized for the space;
- old equipment where replacement would save energy.
Acting on the recommendations isn’t a legal requirement, but many of them save money quickly.
How we help before and after
Our TM44 inspections service covers the parts of the job an engineer is needed for:
- Before: we compile an equipment list with capacities, check whether you’re over the threshold, gather F-Gas and service records and make sure units are clean and accessible. We can arrange the inspection with an accredited energy assessor.
- After: we price and carry out the recommended work: cleaning, control changes, repairs or replacement.
A planned maintenance contract keeps the records an assessor will want to see. TM44 work is quoted at a fixed price after survey.
TM44 and other duties
A TM44 inspection is separate from F-gas leak checks, which depend on the amount and type of refrigerant, and from ordinary servicing. One doesn’t replace the others. Our guide to F-gas regulations for businesses covers leak checks and records, and our legislation page summarises the rest.
Quick answers
Do I need a TM44 inspection?
If the air conditioning in your building, controlled by one person, adds up to an effective rated output of more than 12 kW, yes. Several small units can add up to more than 12 kW.
How often are TM44 inspections needed?
At least every five years, according to GOV.UK.
Can AirCon Doctor carry out the TM44 inspection?
No. It must be done by an accredited energy assessor. We prepare systems, arrange the inspection and carry out the recommended work.
What is the penalty for not having a TM44 report?
GOV.UK says it’s currently £300, with a separate £200 fixed penalty for not producing a report within seven days when asked.
Do I have to act on the recommendations?
It isn’t a legal requirement, but many recommendations reduce energy use and running costs.
Related services
- TM44 air conditioning inspections
- Commercial air conditioning
- Air conditioning maintenance contracts
- Air conditioning servicing
More advice
- Air Conditioning F-Gas Regulations: What Businesses Must Know
- Commercial Air Conditioning: What Businesses Need to Know
- Air Conditioning Maintenance Contract: What It Includes and Is It Worth It?
- Air Conditioning for Offices: What You Need to Know
- All advice
This guide is general information, checked against the sources linked on 30 October 2026. It isn’t legal, tax or financial advice. Rules, grants and product ranges change, so check the current position before you rely on it.