HVAC-R Compressors

Air conditioning compressors and refrigeration compressors are the hearts of air conditioning systems and refrigeration systems. A compressor actually is a pump that moves cool gaseous refrigerant from low pressure side (suction line) through fast moving mechanical parts and squeezes it into high pressure side (liquid line) and raises the temperature of refrigerant. Hot refrigerant vapor (around 20% liquid, 80% gas) leaves compressor in a pressurized state, then condenses into 100% liquid refrigerant when it moves through the fin attached condenser coils. Heat of the refrigerant is released into outside environment when ambient temperature moves through coil fins by condenser fan. Compressor is a key component in all HVAC-R systems. Please check how to do a preventive maintenance for compressor.

HVAC-R compressors can be categorized into 5 types based on their inner designed structures.

  1. Reciprocating Compressor, 2. Rotary Compressor, 3. Scroll Compressor, 4. Screw Compressor, 5. Centrifugal Compressor
hvacr reciprocating compressor

Reciprocating Compressor

Reciprocating compressors (also known as piston compressors) have one or more pistons that compress vapor refrigerant by moving up and down within a cylinder, which operates to an auto engine. Gas refrigerant is drawn into the cylinder through the intake valve(s) when the piston drawn back, and the gas refrigerant is then expelled at pressure through the exhaust valve(s) when the piston returns.

Reciprocating compressors are thought the most energy-efficient type of compressor used for refrigeration and air conditioning applications. There are three types of reciprocating compressors: hermetically sealed, semi-hermetically sealed and open type. Reciprocating compressors are used in appliances, residential, light commercial, commercial air conditioning systems, refrigeration systems, and industrial applications. Refrigeration system reciprocating compressors have square or oval shape cover cases. Reciprocating compressor normally noisy and has higher discharge temperature. Nowadays for residential AC compressors rotary compressor and scroll compressor are more popular.

For better understanding how reciprocating compressor works please click the image to watch a great Youtube video.

hvacr rotary compressor

Rotary Drawing

air conditioner rotary compressor

Rotary Cutaway

Rotary compressor looks round from top and the discharge line is on the top and has an accumulator on the side. Rotary compressors are normally found on window ACs, window heat pumps, mini split ductless revertible systems, RV system.

For better understanding how reciprocating compressor works please click the image to watch a great Youtube video.

hvacr rotary compressor

Rotary Drawing

air conditioner rotary compressor

Rotary Cutaway

Scroll compressor looks round from top and the discharge line is on the top and has an accumulator on the side. Rotary compressors are normally found on window ACs, window heat pumps, mini split systems, RV system.

For better understanding how reciprocating compressor works please click the image to watch a great Youtube video.