Why is it that an air tool will not run when it is cold? Perhaps we could start by defining what is meant by the term cold as it relates to this page?
When it relates to air tools, cold means that the temperature in which you are operating the air tool is around or below 32 deg. F. Since air cools when it flows, if the ambient temperature in which the air tool is being used is around 32 def. F., the problem may occur then as well.
What is the problem when the air tool will not run when it is cold?
Air Compressors Generate Water
Air compressors generate water. A lot of it. The more the compressor runs the more water it makes. Much of that water ends up in the compressor tank, which is why it’s a good practice to drain the compressor tank daily.
Unfortunately for air tool users, lots of that water, in vapor form and in some cases liquid form, travels down the air lines to your air tools, as well.
What happens to water when the temperatures approach the freezing point?
The compressed air, full of water vapor, travels at high velocity into your air tool. The air is already cool from moving, and now it hits the at-freezing-point innards of the air tool, the vapor in the air condenses out and then starts to freeze.
Depending on the temperature of the air around the air tool, and the temperature of the air arriving at the air tool via the air line, the result could be a slow down in the air tool operation, or the air tool may come completely to a halt.
There you are, pushing on the button, or pulling the trigger on the air gun, and nothing happens.
The Air Tool Is Frozen
If the air tool is frozen, disconnect it from the air line and take it into a warm place to thaw.
At this point, it would be a very good idea to put a couple of drops of air tool oil into the connector of the air tool, so that the next time the air tools is operated, fresh oil will migrate through the air tool to lubricate all parts.
Water flowing through the air tool will wash out lubricant, and will certainly rust and susceptible components inside the air tool.
Air Tool Will Not Run When It Is Cold
If the air tool starts to freeze up, it won’t run. What to do?
Many folks have their compressor in a warm location, and the air tool, at the end of an air hose, in an unheated spot. That’s a problem. But even having the compressor in a cold spot too will not eliminate the condensing of warm compressor air in the air lines and the air tool.
It is necessary to completely dry the air so that the DEW point of the air is below that of the air temperature where the air is being used. DEW point is the temperature at which water vapor in the air condenses.
If the DEW point of the compressed air is below that of where the air is being used, then, in theory, no water vapor should form, and your air tool will run when it is cold.
You may need to acquire some fairly expensive compressed air drying equipment to bring the DEW point of the compressed air low enough that you won’t have a problem using the air in sub-zero temperatures.
Failing that, maybe it would be easier to bring your air tool and the work into a heated location?