TM44 air conditioning inspections

TM44 is the accepted methodology for inspecting air conditioning systems, published by CIBSE as guidance for complying with the Energy Performance of Buildings Regulations. In practice the name is used for the inspection itself: an accredited energy assessor examines the system, its controls and its sizing, and produces a report with an assessment of efficiency and recommendations for improvement.

The report is lodged on the government register and a copy goes to the person who controls the system. Only an accredited assessor can carry out the inspection.

Status: LawAir conditioning systems with an effective rated output above 12kW must be inspected by an accredited energy assessor at intervals of no more than five years. The assessment covers all systems in a building, so several smaller units can bring a building into scope together.

It falls on the person who controls the operation of the system, which is not always the building owner. In a let building it may be the tenant, depending on the lease and on who operates the plant.

That ambiguity is the usual reason it goes undone. Both parties assume the other holds it.

An assessment of the efficiency and sizing of the system, with recommendations for improvement. The recommendations are not mandatory.

That is the part most people skip, and it is the part with the value in it. An oversized system running inefficiently costs money every day it runs, and the report says so in writing.

The regulations are enforced by the local weights and measures authority, usually trading standards. A building without a valid inspection report can be issued a penalty charge of £300, and the charge can be repeated while the report remains outstanding.

Enforcement is not the main cost of ignoring it. An oversized or poorly controlled system spends more than the penalty every year it runs, which is what the report is there to show.

We establish which systems are in scope across an estate, whether valid reports exist, when they expire, and where the obligation sits under the leases. The inspection itself is carried out by an accredited assessor. Where the recommendations point at wider savings, the findings feed into an energy audit of the building.