Importance of Cleaning Air Cooled Condensers on All Refrigeration Systems
By Glen Barkhan
There is an important need for regular maintenance of some refrigeration components, especially the cleaning of the air-cooled condenser. Failure to keep the condenser clean will result in abnormal operating temperatures and system pressure resulting in compressor failure and extremely high service repair costs which can be avoided with preventative maintenance checks.
For a refrigerator, it is important to keep the condenser clean, just as it is important to keep the water level up in the radiator of a car. Most manufacturers recommend at regular intervals, not exceeding six months, and more frequently in dusty areas, bakeries, fish and chip shops, commercial kitchens etc. to remove the grill that is placed in front of the condenser- the condenser being a metal finished assembly having a copper tube running through the fins, and similar in appearance to the car radiator. Ensure that there is adequate fresh air flow into the condenser and the hot exhaust air can escape freely without recirculation.
Dust usually forms a coating over the condenser, which may be removed by brushing or vacuum cleaner. Sometimes this dust collects within the fins and must be removed. If using a brush always brush parallel to the aluminum fins and never across as this will bend the thin aluminum material and reduce air flow through the condenser. If the condenser is blocked with oil you will need to switch the system off and use a suitable degreaser for cleaning. This can be a very messy procedure but must be done thoroughly in order to maximize system performance and extend the useful life of the compressor.
A vacuum cleaner will usually pull dust out provided the condenser has not become thoroughly clogged. If this occurs, it may be necessary to use a high-pressure gas to blow this dust out.
After cleaning, always check to see that the condenser is clean right through the fins, a torch usually being needed to ascertain this. Refit the grill in the front of the condenser when cleaning is completed.
Some small low temperature cabinets (chest freezers) do not have a finned condenser, but a plate, or wire type of condenser, similar to those used on household refrigerators, or alternatively; have the outer skin of
the refrigerator as a condenser. This is usually evident by a slightly warmer outer cabinet temperature than that of the surrounding objects. Some new systems are fitted with “reversing” condenser fan motors that can reduce the frequency of having to clean condensers.
Note: Some new quality systems are fitted as standard with an overheat temperature sensor that will switch off the compressor to protect it from damage due to overheating.
Glen Barkhan, a qualified refrigeration engineer. He spent several years as General Manager of SKOPE Refrigeration Australia and was responsible for sales and development of equipment in Australia, New Zealand and the Asia Pacific Region