So, your air compressor will not start when it is cold? Or, if it starts at all, it is sluggishly.This can happen when the compressor is a oil-lubricated model.
If the compressor is stored in an uninsulated garage or other outbuilding when the outside temperature drops into the low 40's (F), or even colder.
Now, let's take that same compressor and put it in the unheated garage. And, it is mid-January in North Dakota, for example. Think it is going to be cold in that garage?
What is an oil-lubricated compressor lubricated with?
Oil, you answer! And, you already know what happens to oil when it gets cold, don't you? The colder it gets, the more that oil thickens. If it is cold enough, that oil will freeze almost or completely solid.
Now, you have the internal workings of your air compressor essentially stuck in a cold, thick oil mass, and you throw the switch to start it up.
Your air compressor is trying to start. It just cannot get enough oomph out of the supply circuit, even with the capacitor kicking in its charge, to start the motor turning against the added load of the frozen or thickened oil. The compressor motor continues pulling more amps in trying to start when so very cold, until the circuit breaker or fuse lets go.
You know how difficult it is to start your car on sub-zero days? Your oil-lubed, and even some non-oil-lubricated models will respond to the cold the same way.
If you are having a problem getting your air compressor to start when it is really cold, warm it up! Bring it into a heated area for an hour or so before you need to use it.
Both your compressor start circuit and the mechanical parts of the air compressor will thank you for it.