Like all complicated machinery that gets lots of use air conditioning needs regular servicing from a professional. The primary reason for this is to keep the system operating efficiently (and therefore cheaply) and avoid expensive breakdowns. For this reason, a full service every 6 months to 2 years (depending on the age of the unit) makes financial sense over the life of the unit.

If your environment is particularly dusty or greasy (for example as a result of food preparation), you may need more frequent servicing. Filters should be inspected, cleaned or changed at least every 3 months (and some manufacturers recommend sooner). A well-maintained system will duly reward you with reduced running costs but the health benefits to a family or a workforce can be impossible to put a price on.

In this guide, I want to look at air conditioning system servicing, what it entails and why it’s so important.

Statutory Requirements may Affect your Schedule

Buildings with more than 12kW of cooling (nearly all buildings with an air conditioning system in other words) need to satisfy the requirements of the Energy Performance of Buildings Directive, which is laid out in technical manual TM44 available from the Chartered Institute of Building Services and Engineers (CIBSE). These include a regime of regular maintenance and inspection.

Depending on the system, there may also be statutory requirements specified within F-gas Regulations and for many public and commercial buildings, there are also other workplace responsibilities as stipulated by the Health and Safety Executive which may include the use of and maintenance of air conditioning systems.

Devising a structured maintenance schedule with the help of an air-conditioning professional makes it easy to budget while ensuring the uninterrupted efficiency and productivity of the plant or office complex. What’s more, research has shown again and again that comfortable workers are happier and more productive employees.

What does a Professional Service Actually Entail?

A professional service engineer doesn’t just look at your condensers, evaporators and filters. He or she will take various readings around your home, office building or factory floor, making a note of the airflows, temperatures, humidity or any other factors that become apparent.

Within the system itself, temperatures, refrigerant pressures and power usage may need to be recorded and checked against the design specifications and requirements of the system.

By logging all these details regularly, you can build up a picture as to how the system needs to be operating and compare it to any potentially detrimental trends that may need investigating. By identifying them early, preventative intervention can be planned.

Caring for your System Components

Routine duties will include checking that filters are in good condition and adequate for their purpose, which could vary according to the operations you are carrying out. Clogged filters, grilles and ducts force the system to work harder, pushing up your running costs while reducing the lifetime of system components.

Some types of filter need regular replacement while others can be washed, but cleaning entails rather more than running them under a tap. Your engineer will use, and recommend, appropriate antibacterial detergents or alternative cleaning methods such as vacuuming, depending on the type of filter.

Note that some filter manufacturers recommend cleaning them every 2-4 weeks, so don’t wait a year between service calls before you next give attention to your filters. Similarly, if you have a ducted system, your ductwork may need inspection and cleaning on a more regular basis.

Leaving parts of the system wet by wiping them with damp dirty cloths can be a mistake, encouraging mildew to develop. This can damage components or risk introducing toxic spores into your air supply. Your engineer will advise you what regimen is appropriate for your system and the correct methods to apply.

Your engineer will also check your condenser unit and heat exchanger. These must be in good condition and unobstructed by windblown debris (or wasps nests!) to keep operating at the lowest possible cost. It surprises some owners to learn that even placing bins close to an outside condenser can affect the airflow it receives, thereby pushing up operating costs.

Any pooling of humidity carries serious risks both of corrosion and of harbouring dangerous microorganisms such as Legionella. Drip trays will be inspected and cleaned and drainage pipes checked to ensure waste fluids can easily drain away.

Your engineer will make a point of checking the condition and electrical safety of all powered components: which is important to meet fire and electrical safety standards and ensure the system doesn’t cause disruption and data loss by provoking power surges as items switch on and off.


Regular refrigerant checks are crucial: they are expensive to replace if they leak out and pose environmental hazards. F-gas regulations have become stricter and will probably continue to do so. As an air-conditioning professional, your engineer will be aware of the latest statutory requirements regarding the handling, recycling, replacement and disposal of refrigerants. They will also be able to warn you of any impending necessity to find a replacement for your existing refrigerant if it is going to be affected by new legislation, or on potential price and performance improvements as new refrigerants become available.

Experience following the phasing out of R22 refrigerants in 2015 showed that prices for alternative refrigerants can rise sharply when demand increases suddenly. Early warning of a need to change could save you money.

Air conditioning systems get a lot of use especially with the long heatwaves the UK is set to experience more frequently. Getting them regularly serviced isn’t just about compliance, but will save you money in the long term and avoid costly and disruptive breakdowns.

If you’d like to know more about our commercial air conditioning services, then drop us a call or an email today.