Method for adding AC compressor oil

AC compressor

You probably don’t often think about how your air conditioning system makes cool air on a hot day.  That is, until it stops working and you’re left arriving at your destination with the sweaty imprint of where your seat belt crosses your shirt.  It really is a relatively simple concept that causes your air conditioning system to work, but it requires a few unique pieces of equipment to work properly in your car.

Most refrigeration systems, including the air conditioner in your car, work on the simple principle that as a gas expands its temperature drops, scientifically called the Joule-Thompson effect.  You’ve probably seen this in effect if you have ever used a CO₂ fire extinguisher.  As the gas is released, the remaining CO₂ in the extinguisher can expand, causing the fire extinguisher to cool off.  The opposite is also true.  As a gas is compressed, it will heat up.  This is the same principle that causes a diesel engine to work, and can even be seen when using a bicycle pump to inflate a tire.  Notice the pump and the hose will get hot partly due to the compression of the air.

The refrigerant in your air conditioning system gets compressed by your AC compressor where it also heats up.  It then is cooled back to atmospheric temperature in the condenser at the front of your vehicle.  The atmospheric refrigerant is then allowed to expand through an expansion valve or orifice tube.  This expansion causes the refrigerant to cool below atmospheric temperature where it then travels to the evaporator which is inside the cabin of your vehicle.  Cabin air is passed over the evaporator, causing the air to cool and the refrigerant to return to atmospheric temperature.  From there it returns to the compressor to start the process again.

Your air conditioning compressor is the only moving piece in your air conditioning system but without it, the process wouldn’t be possible.  The air conditioner compressor is usually mounted on the front of the engine block where it can be turned by a belt on the engine.  The compressor has a pulley and clutch assembly on the front to allow the belt to always be attached to the engine, and to also allow the compressor to engage and disengage with the clutch.  The RPM your engine is turning, and the amount of cooling load on your air conditioning system will determine how often the compressor is engaged or disengaged.

Cycling your AC compressor on and off like this unfortunately adds a lot of wear and tear.  It also functions in a very high pressure system through a variety of temperatures and has to live in an environment that is constantly vibrating and sustaining impacts from your engine running and your car driving down bumpy roads.  This is a difficult life for any pump or compressor so it’s important to take care of your AC compressor.

The best way to ensure the long life of your AC compressor is to ensure that you add adequate oil any time you add refrigerant to your system.  If you’ve discovered a need for more refrigerant in your vehicle, add BlueDevil Red Angel One Shot.  Red Angel One Shot has the correct proportion of refrigerant and an advanced leak sealing agent that works as a lubricant until there is a leak.  If you have evacuated your air conditioning system, use BlueDevil’s Red Angel Oil injector to add Red Angel A/C Stop Leak to your system, ensuring lubrication and leak protection for your vehicle’s air conditioning system.