Importance of the Liquid Line Filter Dryer

Importance of the Liquid Line Filter Dryer

In refrigerant units with an expectation of system servicing, you'll find a filter dryer installed on the liquid line. As its name suggests, it serves two important functions: filtering contaminant particles out of the liquid refrigerant and removing water moisture from the system.

Contaminants can enter the refrigeration system during manufacturing and assembly, during the wear and tear of optimal use, or whenever suboptimal conditions cause damage to machine parts. The filter dryer stops all particles large enough to damage the system -- particles 20 microns or greater.

The filter dryer contains a group of molecular sieve beads that can take up a very large amount of water, effectively removing it from the system. Over time, moisture would otherwise accumulate and cause the formation of corrosive hydrochloric acid, obstructive ice crystals and system freeze-ups.

When we change out a system, we install a liquid line filter drier at the air handling unit, also. The drier is then in a less corrosive environment. When the liquid line filter drier that is installed in the condensing unit from the factory, leaks, we remove that drier (because there is one at the air handling unit that is performing its job) and we install copper in it's place. This way the copper will not rust and leak, so that our customer do not have to pay for more refrigerant.

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