Home Guides Home Home Improvement Can a Central Air Conditioner Compressor Motor Be Rebuilt? Email Reddit Central air conditioner motor compressors can be rebuilt. Whether you can rebuild a central air conditioner compressor motor is not a simple "yes" or "no" question. No, it cannot be rebuilt in the field when servicing a central air conditioning system. Defective motor compressors are replaced in the field with new or reconditioned units. The malfunctioning motor compressor is sent back to the factory to be reconditioned, then sold as a reconditioned unit. No Full Servicing The motor compressors for central air conditioning units are hermetically sealed units with no user-serviceable parts. The motor and compressor are contained in the same housing with the housing halves welded together. Field servicing is limited to replacing the motor compressor’s start relays, run capacitors and starting capacitors. Remanufacturing Special tools and jigs are required to cut open the housing so defective parts can be replaced.

After this, reconditioning special welders are used to weld the housing together again. The special tools and jigs are quite expensive, and it would not be cost effective for the average service shop to purchase them. : Air Conditioner Compressor, A Troubleshooting GuideInspectAPedia: Air Conditioning and Heat Pump Compressor/Condenser Unit RepairsAmerican Hermetics: Our Remanufacturing Process -- The American Way Photo Credits Comstock/Comstock/Getty Images Suggest a CorrectionA burned out or faulty air conditioner compressor can result in noises coming from the appliance, hard starting, or lost cooling capacity. A compressor draws refrigerant gas from an air conditioner’s components and compresses the low pressure refrigerant to high pressure and moves it through the system. Regular inspection and maintenance practices, such as checking compressor support pads help to avoid such problems. While the compressor failing is one of the worst case scenarios, there are other possibilities.

A problem or change in an air conditioner's performance could be symptomatic of something minor. Carry out simple checks to find out what's wrong with the appliance and if it is something small and fixable.air handling unit model number For one, verify that the unit has electrical power. running ac unit without windowMake sure all control settings are properly adjusted. how much does a furnace and ac unit costFinally, check the other components like the air filter, duct work, and blower fans. If any one of these things seems out order, start investigating further in that direction. You may be able to save yourself the time, money, and headache that comes with the compressor. When your unit isn't cooling to the same degree as it should be, the issue may stem from an inability to maintain correct pressure in the compressor.

Both abnormally high and abnormally low discharge pressures can be an signs of a problem with the air conditioner compressor. Such information can be verified by checking the pressure gauges on your unit. Consult your owner's manual as it will tell you precisely what the pressure gauges should read when the unit is functioning at its best. If it does ultimately end up being an issue regarding a lack of correct or consistent pressure, a service technician can help correct the problem. If the air conditioner compressor is sluggish or remains in the “on” cycle but little or no cool air actually comes out, the appliance might have loose or worn compressors. True, this is still a compressor issues, but it's not as condemning since consequences like this are expected from regular wear and tear. Avoid this problem by installing or replacing gauge ports on the compressor. A burned out compressor often originates in the electrical system of the unit. Any damage or exposure of the motor's wiring can result in a burn or short between the compressor and the steel parts of the motor.

When this happens, the unit won't start up at all. Avoid this problem by inspecting the electrical system of the air conditioner regularly. This is commonly referred as hard starting. The compressor usually stutters and may not come on efficiently. If the problem is continuous, take a look at the fuse and the wiring. Replace the fuse if necessary and make repairs on the wires. The air conditioner compressor may fail in case of an overload or if it overheats. This happens when there is an electrical fault within the appliance. To check for this problem, locate the motor and look at the reset button. If there is a fault, it pops out. Wait for it to cool down and push it back in. Always maintain the electrical system of the air conditioner in good condition to avoid this problem.Refrigeration compressors and air conditioning compressors provide air conditioning, heat pumping,  and refrigeration for large-scale facilities and equipment. They use compression to raise the temperature of a low-pressure gas, and also remove vapor from the evaporator.

Most refrigeration compressors (refrigerant compressors) are large, mechanical units that form the heart of industrial cooling, heating, ventilation, and air conditioning (HVAC) systems. Many air conditioning compressors are also large-scale mechanical devices; however, these compressors are designed specifically for air conditioning systems and do not provide heating or ventilation functions. Refrigerant compressors work by taking in low pressure gas on the inlet and compressing it mechanically.  Different types of compression mechanisms are what differentiate compressors (discussed below). This compression creates a high temperature, high pressure gas - an essential step in the overarching refrigeration cycle. The refrigeration cycle or heat pump cycle is the model  describing the transfer of heat from regions of lower temperature to regions of higher temperature. It defines the operating principles behind refrigerators, air conditioners, heaters, and other "heat pumping" devices.

This diagram presents a visual overview of the refrigeration cycle: The letters A-D indicate the different system components. The numbers 1-5 indicate the different physical states of the refrigerant fluid as it moves through the system. This video provides further explanation of the refrigeration cycle: Video Credit: Learn Enginering / CC BY-SA 4.0 Temperature-entropy and pressure-enthalpy diagrams are often used to construct and describe these systems. They define the properties of the fluid at different stages in the system. The diagram below depicts temperature-entropy a typical refrigeration cycle: The following diagram shows pressure-entropy of a typical refrigeration cycle: There are a number of different types of compressors used for refrigeration and air conditioning. Like pumps, all "heat pumps" can first be categorized as either positive displacement or non-positive displacement (centrifugal). Positive displacement compressors have chambers which decrease in volume during compression, while non-positive displacement compressors have fixed-volume chambers. 

Beyond this distinction, each type differs based on its specific mechanism for fluid compression. The five main types of compressors are piston, rotary, screw, scroll, and centrifugal. Piston compressors, also called reciprocating compressors, use a piston and cylinder arrangement to provide compressive force - like combustion engines or piston pumps. The reciprocating motion of the piston due to external power compresses the refrigerant inside the cylinder. Piston compressors have a low initial cost and a simple, easy to install design. They have a large power output range and can reach extremely high pressures. However, they have high maintenance costs, potential vibrational issues, and are not typically designed to run continuously at full capacity. Rotary compressors have two rotating elements, like gears, between which the refrigerant is compressed. These compressors are very efficient because the actions of taking in refrigerant and compressing refrigerant occur simultaneously. 

They have very few moving parts, low rotational speeds, low initial and maintenance costs, and are forgiving in dirty environments. However, they are limited to smaller volumes of the gas and produce less pressure than other types of compressors. The following diagram shows rotary vane compressor operation. Screw compressors use a pair of helical rotors or screws which mesh together to compress the refrigerant between them. They can produce high pressure for a small quantity of gas and consume less power than reciprocating compressors. They have low to medium initial and maintenance costs and few moving parts. However, they have difficulty in dirty environments, high rotational speeds, and shorter life expectancies than other designs. Scroll compressors use two offset spiral disks nested together to compress the refrigerant. The upper disk is stationary while the lower disk moves in orbital fashion. Scroll compressors are quiet, smooth-operating units with few moving parts and the highest efficiency ratio of all compressor types.

They also are more flexible for handling refrigerants in the liquid. However, as fully hermetic designs, scroll compressors cannot be easily repaired. They also typically cannot rotate in both directions. Scroll compressors are commonly used in automobile air conditioning systems and commercial chillers. Centrifugal compressors use the rotating action of an impeller wheel to exert centrifugal force on refrigerant inside a round chamber (volute). Unlike other designs, centrifugal compressors do not operate on the positive displacement principle, but have fixed volume chambers. They are well suited to compressing large volumes of refrigerant to relatively low pressures. The compressive force generated by an impeller wheel is small, so systems that use centrifugal compressors usually employ two or more stages (impellers wheels) in series to generate high compressive forces. Centrifugal compressors are desirable for their simple design, few moving parts, and energy efficiency when operating multiple stages.

Usually compressors are designed to work with a particular type of refrigerant. Selecting a proper refrigeration compressor or air conditioning compressor requires finding a compressor rated for the desired refrigerant for the application. Refrigerants are given names such as R-12 or R-134a from the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). Ideal refrigerants have favorable thermodynamic properties and are chemically inert (noncorrosive), environmentally friendly (degradable), and safe (nontoxic, nonflammable). The desired fluid should have a boiling point somewhat below the target temperature, a high heat of vaporization, moderate liquid density, high gas density, and a high critical temperature. There are a number of specifications to consider when selecting compressors. These include capacity, condensing temperature, evaporating temperature, flow rate, and power. Charts like this one are provided by the compressor's manufacturer, allowing engineers to make these adjustments properly once in the system: