Air Conditioning Inspection - Energy Performance

Air Conditioning Energy Performance and Certification
Faq's - Frequently Asked Questions about Air Conditioning Inspection procedures and techniques. See What Systems Require Inspection as part of the EPC for commercial property. This section explains the energy performance of buildings with respect to air conditioning systems installed therein.

Assessment of  the energy performance of an air-conditioning system

For air movement systems: What the Inspector Looks for:

Where installed as part of the system to provide cooling, air movement systems are an important factor in the assessment of the property under survey. In particular the contribution that fans add to the total annual energy consumption of the combined cooling system is likely to be higher than that of the refrigeration plant itself, and so there may be a greater potential for improvement of the system that may be recommended. The assessor will advise on this issue.

Assessing Effectiveness One of the main factors involves the effectiveness of how air is delivered, can play a part in determining the overall efficiency of the air-conditioning system. If it is deemed that air delivery systems are ineffective, plant that is otherwise efficient may operate for longer periods than necessary. The inspector will observe the the condition of, damage to, or blockage of filters and heat exchangers as part of this process, and, in addition the fan type and method of control that is employed in the system.

Ventilation Efficiency

Ventilation air delivery systems need free access to outdoor air for intake. If grilles, screens or pre-filters are damaged or debris partly blocks air flow, additional energy will be required to overcome the extra resistance caused by the restriction to air flow, this may cause the system to under-perform in other ways due to reduced air flow rates, thus reducing overall efficiency.

In systems that provide cooled air, allowing air from locations where the local air temperature may be higher than ambient temperature will add to the energy required to achieve cooling to the required temperature set by temperature controls. Such locations might include positions near busy roads, in car parks, or where the exhaust air from the building could be drawn into the air inlet by the proximity of the exhaust vents.

Air Conditioning Controls

Fundamental to the system as a whole is the method of control. System controls are assessed in more detail by the assessor. In this area there is scope to identify inefficiency due to inappropriate control methods, for example: incorrect control settings and poorly located sensors in the building,  there could be much potential for improvement to the system at a relatively low cost. The assessor may discover ‘faults’ that could be as simple as time-switches or cooling or heating thermostats being set incorrectly, the inspector will not reset them but will report to the building owner or manager the findings in the survey. Such fundamentals could give the assessor an indication of potential inefficiency, ineffectiveness or misuse of the air conditioning system in use in the property. As a general rule (except complex systems) the assessor will examine and note some of the following observations

• Record set temperatures to which the treated spaces are to be conditioned in the building.

• Record time periods during which they are to be conditioned within the premises.

• Note the appropriateness of the control zones, control sensors and their
  locations throughout the installation.

• Any potential for cooling to be operated at the same time as heating in the property.

• Note the method of refrigeration capacity control in the building

• Note the method of air flow rate control in the property being inspected.

If such systems are controlled by a Building Management System (BMS), it may be necessary for the building/facilities manager to arrange for relevant aspects of this information to be extracted from the BMS prior to the date of inspection so that this information is available to the assessor on the day of survey. The inspector will be able to advise on this issue if a Building Management System is in use at the premises.

How to obtain an air-conditioning inspection for commercial premises

Know your responsibilities for ensuring inspections are done. The following outlines the remit for obtaining an energy assessment of the installed air conditioning equipment.
The nominated person who controls the operation of an air-conditioning system affected by Regulations has the  responsibility to ensure that:

• The inspection has been done in accordance with the requirements
  and timetable of the Regulations in force.

• You have a duty to keep the most recent inspection report completed by an energy assessor for your system.

• You must give any inspection report kept by you, to any person taking over your responsibilities with respect to the control of the air-conditioning system in the premises that you occupy.

Find an Assessor (Inspector)

Companies, Contactors and Surveyors of Air-Con Systems for energy assessment purposes as part of an EPC certificate can be located in our Directory, in many cases you can locate a suitably qualified assessor near to your local area. If you are in doubt as to whether an inspection is required as part of the legislation seek professional advice. You may be subject to a penalty or a fine for non-compliance with the regulations.

Refer also to Air Conditioning for further details regarding Refrigeration, cooling, design, engineers, service, installation, maintenance, repairs, inspection, installers, Refrigeration and Cooling, Variable Refrigerant Volume/Flow Systems VRV VRF, Heat Recovery, Ducted Systems, Climate Control Systems, upgrades of New and Existing Air Conditioning HVAC Heating Ventilation plant (AHU) Air Handling Units and controls.