Fixed speed compressors, also referred to as on-off compressors, operate at a single, constant speed. They continuously switch on or off to meet your refrigeration unit’s demand requirements. This means they turn on when needed, operate at full speed until they meet demand, and then shut off again.
The difference between fixed speed and variable speed compressors is their operation. Fixed speed compressors use only one speed while variable speed compressors can adjust their speeds to fit the demand requirements. This means that variable speed compressors are more energy efficient than fixed speed compressors. They also recover more quickly from a door opening, meaning they work better in food service applications than fixed speed.
Compressors come in three types:
Hermetic compressors are completely sealed to protect against the external environment with a welded-shut casing. Because they are completely sealed, the compressor cannot be accessed. This means that if the compressor fails, it cannot be serviced. It must be replaced. Hermetic units are common in consumer appliances like home refrigerators, but they may be used in small, refrigerated displays.
Semi-hermetic compressors have the compressor and motor housed in a sealed shell. But, unlike hermetic models, semi-hermetic units can be opened for diagnostics and repairs. Because they can be maintained and serviced, semi-hermetic compressors tend to last longer than hermetic units.
Open compressors keep the motor and compressor separate from one another. The compressor connects to the motor by way of a belt or crankshaft. Their design allows for easy access to all parts in case of repair. However, because open compressors do not have a sealed shell like hermetic and semi-hermetic units, they are more prone to leaks and damage from debris.
Embraco, a portfolio brand of Nidec Global Appliance, has become a global supplier of refrigeration technology for the residential and commercial cold chain. Their innovative products continue to exceed the demands of the market.
Their quality selection of fixed speed compressors includes the following series: