If you want a reliable air source in your garage, a rotary screw air compressor is definitely a piece of equipment you should have. Even large industrial companies use rotary screw air compressors because of their resiliency and durability. Even still, these machines can have issues every once in a while, and as the owner, it will be very helpful if you know how to track down the problem. Here are a few of the most common problems that can come up with rotary screw air compressors and the facts about issues that you should know. 

Problem: The overload relay continuously trips. 

Cause and Solution: If the overload relay on the compressor is tripping, it means that it is getting too much electrical current. This could be related to faulty wiring, but is most often a sign that the air compressor motor is having issues. Turn off the air compressor and open the motor housing. Reach in and try to turn the motor by hand and make sure there are no obstructions and it turns freely. If it does not, you may have to have a mechanic take a look at the motor to replace anything that could be interfering. 

Problem: You keep getting fluid in compressed air.

Cause and Solution: You could have either water or oil in the compressed air, depending on the problem. Test the viscosity of the fluid by rubbing it between your fingers. If it is oil, check to make sure the oil reserve tank is not leaking and the filter is in good shape. If it is more like water, the condensation trap may be clogged up, which would not allow excess moisture to drain out. 

Problem: Compressor will not load air at all.

Cause and Solution: If you turn on the air compressor and hear it running but you are not getting air in the tank, it is likely that the safety valve of the tank has been through too much pressure and opened up. Depending on the amount of pressure, the safety valve may even be damaged. Check the valve and reseat or replace it if necessary to solve the issue. 

With a little knowledge, time, and attention, you can easily handle a lot of small problems with a rotary screw air compressor on your own. However, if you are having issues with your air compressor that you cannot diagnose on your own, talk to a professional technician for advice or read this post.