Mandatory Energy Inspections has been introduced for all air conditioning systems with a rated cooling output greater than 12 kilowatts. 

One or more air conditioning units within a building controlled by a single person, will count as a single air conditioning system for the purposes of the regulations.

Knowing if your system falls under the regulations and when you will need to get an inspection by, will depend on the effective output of an individual air conditioning unit or system, so when do you need to have your system inspected by, if your equipment has an effective output of greater than 250 kilowatts you must have your first Air Conditioning Energy Inspection carried out by the 4 January 2009.

If your air conditioning system has a rated output greater than 12 kilowatts but less than 250 kilowatts you must have had your first inspection by the 4 January 2011, thereafter inspections will be required every 5 years unless significant alterations / modifications to the system has occurred. For new systems installed on or after the 1 January 2008 the first inspection must have taken place within 5 years of the installation date.

The responsibility for arranging and insuring that an inspection takes place will fall on the person who controls the operation of the system; this is the person who controls the technical functioning of the system and not someone who can just alter the temperature.

Usually the owner of the system will control its operation even if day-to-day operation is contracted out to another person. Where a tenant takes total responsibility for a building and its services, for example, with a full repairing and insuring Lease, then the tenants will control the system