When replacing a failed component or accessory for a compressor, it is always best to use the one specified by the manufacturer. There are some components that may have a universal replacement, but you need to be sure the universal component is the right match for the component that needs to be replaced. The wrong replacement component may not only cause the compressor to not run, but it also could cause damage to the compressor.

When selecting a replacement component, you will need to have the make and model number of the compressor or accessory. If you opt to get an original equipment manufacturer (OEM) component, simply giving make and model to the wholesaler should enable you to get the right component. However, if you choose to try a universal component, it may be helpful to be able to decipher some information from the compressor’s model number.

There is much information about a compressor that can be obtained from decoding its model number. Again, this can be a valuable aid for a technician when trying to select a replacement component. Every compressor manufacturer has its own nomenclature for its series of compressors. The information contained in the model number will vary from manufacturer to manufacturer, so you will need to obtain the coding used for each of the different compressors you service. This is not a difficult task; the information is usually readily available from the manufacturer in their service publications.

Listed here is some of the information that might be obtained from the nomenclature of a compressor’s model number:

• The physical characteristics of the compressor series, such as its footprint, body dimensions, and layout of its stub or service valve connections, which may be useful when determining if the universal component will fit onto the compressor;
• Some model numbers will also include the type of refrigerant originally designed for the compressor;
• Many times, the application range of the compressor can be determined, which identifies if the compressor is designed for high-, medium-, or low-temperature application;
• The Btu capacity is normally included, but, sometimes, instead of the Btu capacity, the model number will state the compressor’s motor horsepower or its displacement;
• Some models will state the type of oil originally included with the compressor;
• Sometimes it will state if the compressor incorporates a permanent-split capacitor (PSC), start, or other motor design. This can help a technician identify which types of starting components are used on the compressor; and
• More than likely, the voltage rating of the compressor will be stated. Again, this can be useful when troubleshooting a compressor and trying to determine if the correct voltage is being applied.

Knowing what you need when using a universal component is key for getting the right component. Your wholesaler can be of great assistance in cross-referencing a suitable replacement, but it is up to you to verify that it will work.