Hi,

A screw compressor that becomes too hot is a very common problem. Fortunately, it is most of the time easy to find the problem.

With the compression of air, a lot of heat is generated. Most of this heat is absorbed by the compressor oil and this heat needs to be removed.

These are the most common causes for an overheating screw air compressor:

1. Too hot surrounding air / bad cooling air flow

The compressor needs cooling air to get rid of it's heat. If the compressor room becomes too hot, the compressor will overheat. If the temperature in the compressor room reaches 40 degrees Celsius (104 F), you can expect compressor problems.

If the compressor sucks air from outside, make sure the ducts are not blocked or too small.

2. Too little oil.

Check the oil level in the separator tank when the compressor is running unloaded. It should be in the upper part of the green indicator.

3. Oil cooling problems.

The most common problem of a compressor that runs too hot: dirty oil cooler.

Open the compressor and check the oil cooler. The compressor blows an enormous amount of cooling air through the oil cooler. It works just like a vacuum cleaner: all the dirt and dust in the air will clog-up the outside of the oil cooler.

If this is the case... clean the oil cooler. You can do this by blowing compressed air through it in the opposite direction of the normal air flow.

While you're at it, clean the after cooler also, they sit right next to each other.

If the cooler was/is clean, but you still have the same problem, it could be that the thermostatic valve is stuck in closed position. Best to replace it then.

You can often check this by feeling (by hand, be careful) on the two hoses that run to and from the oil cooler. When they are only warm (not hot) and about the same temperature, then there is no oil flowing through the oil cooler.

I've attached a picture of an oil cooler and a thermostatic valve so you know what they look like.

These are the most common problems (99%) of overheating screw air compressors. Please let me know if this helped solve the problem

Good luck!

Hi,

We have Worthington Screw Air Compressor RLR 150 EV and we are based in UAE where humidity reaches almost 95%. So the problem we are facing is water is getting inside the separator, oil tank and cooler also.

Our vendor is saying this is because of high humidity and Worthington VSD compressor has this drawback.

Can you please help how to fix this problem.

The compressor is installed in an open area under the shed which is closed by one side.