What is a liquid line filter drier?

Asked By: Hector Katznelson | Last Updated: 2nd February, 2020
Category: home and garden indoor environmental quality
4.8/5 (128 Views . 18 Votes)
A filter-drier in a refrigeration or air conditioning system has two essential functions: one, to adsorb system contaminants, such as water, which can create acids, and two, to provide physical filtration.

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Just so, how do I know if my liquid line filter drier is clogged?

A symptom of a clogged liquid line filter drier is a temperature drop across the filter drier. Filter driers are typically shaped like a hot dog and are about the same diameter.

Furthermore, what's inside a filter drier? The most common materials used in filter drier construction are activated alumina and molecular sieve. Activated alumina is used for removing organic acid molecules from refrigeration systems.

Similarly, which direction does a liquid line filter drier go?

Point the arrow in the correct direction. Suction driers point towards the compressor and away from the evaporator. Liquid line driers point toward the metering device and away from the condenser. A liquid line drier goe in the liquid line NOT in the discharge line.

How do I know if my filter drier is bad?

Symptoms of a restricted liquid line include:

  1. A higher than normal discharge temperature;
  2. High superheats;
  3. Low evaporator pressures;
  4. Low condensing pressures;
  5. Normal to slightly high condenser subcooling;
  6. Low condenser splits;
  7. In some cases, a local cool spot or frost after the restriction;
  8. A low amp draw; or.

33 Related Question Answers Found

What happens when orifice tube is clogged?

Clogged Orifice Tube. The orifice tube can become restricted and clogged with debris. A clogged orifice tube is typically caused by compressor failure. When this happens, little pieces of metal and aluminum shrapnel will be found in the tube's screen filter.

Is the liquid line the suction line?

The larger line typically carries a cool gas and is insulated. This is commonly referred to as the suction line, but it is also called the return line or vapor line. The smaller uninsulated line typically carries a warm liquid. It is most often called the liquid line.

When should I change my AC filter drier?

A filter drier needs to be replaced anytime the air conditioners refrigeration system is worked on. When you replace a compressor, a TXV or any time the system is open to the atmosphere, change the filter.

What happens if expansion valve goes bad?

Too much refrigerant flow and the evaporator core will freeze over; too little and the evaporator core will overheat and compromise the efficiency of the AC system. When the expansion valve fails or has any issues, it can cause problems with the functionality and performance of the AC system.

What are the symptoms of a bad AC dryer?


Usually the receiver dryer will produce a few symptoms to the system that will alert the driver of a potential problem that should be inspected.
  • Signs of refrigerant leakage. One of the first symptoms that a bad or failing receiver dryer will display is leakage.
  • Rattling noises.
  • Moldy smell from the AC.

How does a liquid line drier work?

Liquid Line Type is placed after the condenser coil and before the expansion valve. The liquid refrigerant that flows from the condenser to the expansion valve is filtered from particles and moisture before entering it. Good filter will filter out particles that are 20 micron or above from the system.

What causes the liquid line to freeze?

Once the refrigerant absorbs the heat, the (now) cool air re-enters your home. But if there is a lack of warm air blowing across the evaporator coil, then the refrigerant gets too cold, which can cause the refrigerant line that connects to your outdoor unit to freeze.

What does a suction line filter drier do?

These suction line filter-driers include protection from moisture and organic or inorganic acids, resulting from burnouts, or chemical changes in the system refrigerant or oil. They're especially suited for system cleanup after a burnout, or when major work has been performed on the system.

Where is a filter drier located?

Filter driers are usually found in the liquid line and occasionally also in the suction line of the compressor. The suction line is the segment of refrigerant piping leading to the compressor inlet, and the liquid line is the segment following the compressor outlet.

Where does the filter drier go?


Where is the Drier Usually Located on an Air Conditioning, Heat Pump, or other Refrigeration System? The drier is installed at the coolest location on the system, on the liquid line, outside of the refrigerated space, and ahead of any refrigerant metering devices like thermostatic expansion valves or capillary tubes.

How do you install AC drier?

Part 2 of 3: Installing the new receiver/drier
  1. Step 1: Measure the amount of oil in the receiver/drier.
  2. Step 2: Add oil to the receiver/drier.
  3. Step 3: Replace the pressure line o-rings.
  4. Step 4: Install the receiver/drier.
  5. Step 5: Reinstall the lines.
  6. Step 6: Reinstall the electrical connectors.

Where is the sight glass located?

In a system with an expansion valve, a sight glass is usually fitted in the liquid line immediately after the filter drier.In theory, the sight glass can be fitted at any desired location on the liquid line. However, placing it close to the expansion valve is especially advisable.

Which way does Freon flow?

The refrigerant is pushed through the exhaust valve into the condenser. Both the intake and exhaust valves are designed so that the flow of the refrigerant only travels in one direction through the system. Condenser: The condenser removes heat given off during the liquefication of vaporized refrigerant.

What is a refrigerator dryer?

As the name implies, a refrigerated air dryer works by cooling down the air (like a refrigerator). The warm wet air enters the dryer, where it is cooled down to about 3 degrees Celsius. All water vapor that was in the air condenses into water. Much like your window does on a cold day.

Where do you put a filter drier on a heat pump?


A filter-drier should be installed in the suction line to clean up a heat pump after severe hermetic motor burnout. First, make sure the burnout is “severe” by testing the acidity of the oil from the burned out compressor using the Parker Sporlan TA-1 Acid Test Kit.

What is the difference between a strainer and a filter drier?

The indicator is a porous filter paper impregnated with chemical salt that changes color when exposed to moisture 20-25) What is the difference between a strainer and a filter-drier? Strainers have no desiccant inside to absorb the moisture, they are simply filters used to prevent solid particles.

What should the temperature difference between the drier filter?

Recommended: Temperature or Pressure Drop across a Drier is No More than 2 psig or 2 Degree's F. Commercial and Industrial Refrigeration. Commercial and Residential Air Conditioning.