The mighty drier, not the most complex part of the A/C system, but extremely important to keep the system running at optimum performance. When you search the Highgate Air website for driers, you will find 941 results to suit all imaginable cars, trucks, mining and agricultural vehicles. This essential component can often be overlooked, but it’s important to change driers regularly.

 


The function of the drier.

These tiny but mighty products are in every A/C system and have the hefty responsibility of ‘drying’ any moisture in the A/C system (hence the name!). If moisture remains in the system, it can freeze inside the pipe, restricting refrigerant flow. When in contact with oil, moisture will also cause sludge to build up in the system.

 

The drier, sometimes referred to as the receiver drier, or filter drier, is also able to filter out particles to prevent them from flowing through the system. This can help with metal filings, as featured in our recent blog on compressor failure.

 

Driers come in two varieties - upright and in-line. The main aim is to ensure installation allows for liquid refrigerant flow to the TX valve. The drier is positioned between the condenser and the TX valve at the evaporator and enables the refrigerant flow in that order.

 


Why driers need to be changed regularly.

 

Since a large part of the drier is filled with desiccant, any time the A/C system is open and exposed to air, the desiccant will quickly absorb moisture. If it becomes saturated, it will no longer be able to absorb moisture from the refrigerant, and moisture could begin circulating the system. Moisture in an A/C system is known as the 'enemy of refrigeration'. Mixing moisture with oil and refrigerant produces an acid, which will corrode systems from the inside and damage key components such as condensers, evaporators and TX valves.

 

The drier is easily accessible in the system and should be regularly inspected and replaced when necessary. When the system remains un-opened, we recommend replacing the drier every two years to keep the system operating effectively and to avoid any major faults occurring. When there’s a requirement to flush the system (any time you find a fault), the drier should also be replaced.

 

Changing driers at regular intervals will ensure optimal air conditioner performance, and is good practice for preventative maintenance to avoid major faults. Keep adequate stock of driers on-hand for the vehicles you service and to ensure you can complete an effective A/C service at any time.

 


Need to stock up? Search Highgate Air for all your drier needs, including replacement desiccant bags and more.