The importance of cleaning air handling units to maintain efficiency

Sajjun Lohia, Sales and Marketing Coordinator at Climalife discusses the importance of cleaning air handling units to maintain efficiency


HVAC systems, under normal conditions, will inevitably accumulate dust and debris hence they should be cleaned once or twice per year. The benefits of cleaning include health promotion, maximum reliability as well as efficiency of the system.

A well-maintained system offers many advantages such as, improved energy efficiency, longevity of system life and preserved performance. In addition, good maintenance can help to prevent contamination and remove offensive odours.

With regards to air handling units, continued upkeep could reduce the risk of costly repair bills. It would also mean units would be working at maximum efficiency as a result, keeping energy costs down.



Coil Cleaning

Coils are in direct contact with the air flow pathway in all ventilation systems and thus should be cleaned regularly. Cleaning is important as coils have a direct impact on the rate of air flow, efficiency of heat transfer and indoor air quality. Dirt or debris on the coils add an extra layer between the air that blows over the coils and the refrigerant that absorbs and releases the heat. Over time, the accumulated dirt acts as an insulator making heat transfer less effective. Poor heat transfer leads to less efficient operation meaning the unit is running longer. But the unit is still required to produce the same degree of cooling or heating, meaning the system is now working overtime to achieve the same target temperature.


Frionett Coil Cleaner


Unclean coils can lead to higher energy bills and poorer air quality yielding reduced system reliability. Moreover, low levels of contaminants on the coils can elongate run times at increased temperatures and pressures, subsequently shortening system lifetime.

A powerful cleaning product such as Frionett® Coil Cleaner from Climalife, could be used for the degreasing of indoor unit coils. The cleaning and degreasing ability of Frionett® works to eliminate dust, debris and other pollutants thus improving airflow. Unimpeded airflow is paramount to optimising the operating temperature and cooling efficiency. Overall reducing wear on the system and improving product lifespan.


Don't forget the outdoor unit condenser coils!


Frionett Coil Condenser


Paired with cleaning the air handling unit, ensuring the outdoor unit condenser coil is kept in good condition is also critical to optimum system efficiency and reliability. Reduction in air flow through the outdoor unit will rapidly diminish the cooling performance and negatively impact energy efficiency.

Even moderate fouling of a condenser will lead to an increase in condensing temperature of the system. Equally if the system has a high/condenser pressure controller, checking the setting is not causing the system to operate at excessively high conditions or is set correctly for the refrigerant used (for example after a retrofit) can have a big impact.

Figure 1 below shows the impact of increasing condensing temperatures with R-449A at low and medium temperature conditions. Even a very small increase in the condensing temperature can lead to significant decreases in energy efficiency, for example, an increase from 25°C to 27°C condensing temperature can lead to a 5-8% loss of compressor energy efficiency.



Pressure increase caused by condenser fouling is easily prevented by regular use of cleaning products such as Frionett® condenser coil cleaner from Climalife which has been specially formulated to prevent this problem, acting to remove outdoor pollutants from the external units of air-conditioning and refrigeration systems.


Just a gentle reminder...

With rising energy costs on everybody’s minds you probably want to minimise your energy bill and explore opportunities to save money. You may think it costs a lot to get your system serviced however it could cost more in the future, if it was to breakdown or become less reliable. A simple clean using quality cleaning products such as Frionett® Coil Cleaner or Coil Condenser, as well as regular servicing, could help to prolong the life of your system, giving you peace of mind and saving you money.

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