How to Replace a Refrigerator Compressor: What You Need to Know

Are you wondering how to replace a refrigerator compressor? Is your refrigerator not cooling enough? Is your refrigerator not running? Is your fridge make a loud noise? Maybe the problems come from the compressor and need to replace your fridge compressor.

In this article, we’ll show how to replace a refrigerator compressor step-by-step, we’ll start with removing the old compressor and then removing the filter drier after installing the new compressor and filter drier, so please follow these instructions below:

The compressor is the soul of the whole refrigerator. If the compressor of the refrigerator is faulty, it will lead to the abnormal operation of the refrigerator and affect the cooling effect.

How to replace a refrigerator compressor

How to replace a refrigerator compressor Step-By-Step

1. How to remove refrigerator compressor?

we recommend that the used refrigerant fluid be collected for later recycling or incineration, according to the following procedure:

  • Install a perforating valve in the compressor process tube.
  • Connect the performing valve to the recovery equipment that is then connected to the receiving cylinder.
  • Connect the recovery equipment.
  • Open the receiving cylinder valve and then the performing valve.

It’s very important to keep the recovery equipment operating as long as it is necessary to collect all refrigerant.

The duration of this process will depend on the equipment used and the refrigeration system.

Once you do that now it’s time.

To remove refrigerator compressor:

1. Loosen the points where the compressor is fixed to the system.

2. Undo the connections from the electrical starting and protection devices.

3. Remove all oxidation and paint using sandpaper in the brazing region, to facilitate brazing later.

4. Warm the brazing region In order to separate the compressor from the system’s piping.

After cooling

5. Close off the compressor tubes and system tubes with rubber plugs.

6. Loosen the locks that fix the compressor base to the system.

2. How to remove filter drier on a refrigerator compressor?

Remember that changing the compressor also requires a change of the filter drier, in order as follows:

  1. Slowly warm the soldering region of the capillary with the filter dryer  at the same time, pull the capillary with pliers, using moderate force not to break it inside the filter drier.

Preferably, during the removal of the capillary

2.  Make nitrogen circulate to prevent the capillary end from blocking

After cooling

  • Close off the compressor tubes and system’s tubes with rubber plugs.

Another procedure that normally prevents blocking the capillary is to:

1.  Remove the end that had been brazed to the filter drier

2.  using a file make a small groove around the capillary and bend it until it breaks.

Nevertheless, in cases of success of the tube will significantly alter the capillary flow and jeopardize the performance of the refrigeration system.

When removing the filter you must not heat it unnecessarily otherwise water retained in it will enter the system piping.

Notes:

Never use alcohol or other byproducts as a solvent, they cause corrosion on the compressor tubes and metallic parts and the electric insulation becomes brittle.

Only use filters with descants suitable for the type of refrigerant.

3. How to clean used refrigeration compressor system?

Not all compressor changes require cleaning the low and high-pressure tubes.

Cleaning is recommended in cases where it is suspected that there are high levels of contamination of water and residues resulting from the burnout of the compressor winding.

To protect the environment and reduce expenses when changing compressors, fluid for cleaning the unit’s components must circulate in closed circuits.

At the stage when replacing the compressor, the return line shall be disconnected from the compressor and the capillary disconnected from the filter drier.

To  complete the cleaning operation, proceed as follows:

  1. Place a fast coupling on the return line and connect it on the cleaning machine’s outlet side.
  2. Connect the capillary to the cleaning machine’s suction side, leaving it operating for around 15 minutes.
  3. Blast some nitrogen into the circuit to remove any cleaning fluid residue.

Lastly, the condenser must be cleaned.

To do so, you must repeat the previous operations, connecting one end of the condenser to the outlet side and the other to the cleaning machine’s suction tube.

4. How to install filter drier on refrigerator compressor?

  1. Make a small bend in the capillary to prevent it from going too far into the filter, approximately 15 mm.
  2. Using a clamp, open up the two sides of the filter drier brazing.
  3. Braze the filter into the condenser and capillary.

Do not unnecessarily heat the body of the filter dryer, and take great care not to block the tubes.

  • Install the fast coupling to make a vacuum on the high pressure side.
  • The filter dryer must be installed in the vertical position with capillary at the bottom.

This position prevents the desiccant grains from rubbing and releasing residue, it also helps equalize pressure faster.

The system is now ready to receive the new compressor.

  • Install it in the correct position and fix it to the base.
  • Braze the suction and discharge tubes to the respective compressor tubes.
  • Also braze a tube of approximately 100 mm to the process tube.

For all the other ends of this tube, install a fast coupling or similar register to make the vacuum and gas charge.

5. Caution with vacuum and refrigerant fluid charge.

Never use the new compressor as a vacuum pump, it may absorb dirt and water from the tubes, which will be detrimental to its operation and working life.

6. Vacuum pump

  • Always use a high vacuum pump
  • Whenever possible, make a vacuum on the high and low side.
  • Use a hose exclusively for each refrigerant.
  • Apply vacuum until 500 µm Hg (29.90” Hg), never less than 20 minutes at this level.
  • It is recommendable to install a check valve at the inlet of the vacuum pump.

7. Refrigerant fluid charge

In domestic refrigeration system’s as with most work with little refrigerant fluid less than 350 g (12.35 ounces), and use a capillary tube as a control element, the performance of the refrigeration system will very much depend on the refrigerant fluid charge used.

Now, with alternative refrigerant fluids, it is even more important to proceed correctly and use proper equipment for this operation.

Example:

The system with an internal volume of 280-300 liters normally operates with 90-120 grams (3.2-4.2 ounces) of R 12 refrigerant.

With R 600a, the systems in this range of inside volume may only have 36-48 grams (1.3-1.7 ounces), which is approximately 40% of the R 12 charge.

In relation to the original charge with R 12, the R 134a refrigerant fluid charge is approximately 90% and blends 80%.

This fact confirms the need for correct procedures and proper equipment for successfully charging a refrigerant fluid.

8. Main procedures to recharge refrigerant fluid.

If you are using scales and charge receiver cylinder:

  1. Weigh the empty cylinder.

The correct charge will be the quantity supplied by the manufacturer plus the weight of the empty cylinder.

  • With the compressor switched off, connect the receiving cylinder to process tube.
  1. Open the valve of the receiving cylinder and wait until the pressure has equalized (cylinder/sealed unit).
  • Close the receiving cylinder valve and switch on the compressor.
  • Gradually open the receiving cylinder valve.
  • After removing the cylinder, weigh it to make sure that it is completely empty.

If using a charging cylinder with graduated band:

  1. Write down the volume of the column relating to the refrigerant to be used.
  2. Connect the cylinder to the process tube.

With the compressor switched off, open the register until the quantity stipulated by the manufacturer flows out or until the pressures in the refrigeration system cylinder are equal.

If it equalizes before the charge is totally empty, switch the resistance of the charge cylinder to increase the pressure and release the refrigerant to the refrigeration system, if it is not possible to increase the pressure in the charge cylinder through the resistance, you may lock the register of the charge cylinder, switch the compressor on and then slowly open it until the correct refrigerant charge is transferred.

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Closing the sealed unit:

  1. With the compressor connected, flatten the process tube as close as possible to the fast coupling, keeping the pliers fixed to the tube and switch the compressor off.
  • Break the tube at the first flattened point and check to see if there is any leakage. If not, solder the end of the tube, remove the pliers and check to see if there is no leakage.