Following the emergence of tire pressure monitoring systems and run-flat tires, some people mistakenly think that air compressors are now no longer needed for car tires. Car tires can slowly lose air even in the absence of a puncture, and this can happen at an inconvenient time. Having a portable compressor means that you can fill the car tires at your convenience when you get a flat. Having this device also means you can lend a hand to other motorists. Before picking any particular compressor for tire inflation, you want to be sure that you have the right size air compressor.
For more information on the right size machine for the job, see our comprehensive guide What Size Air Compressor Do I Need? The guide contains 41 real-world use examples and information on the size of compressor you will need for each.
Selecting the Right Size Air Compressor for Filling Tires
If your portable air compressor is to work conveniently, fast, and last long, it should meet certain criteria.
Let us now discuss the most important considerations:
The first concern when you are looking for the best size of air compressor for tire inflation is likely to be the tank pressure given as pounds per square inch of pressure. You want to know the amount of pressure that the item can produce. It is an important factor because if the maximum PSI from the compressor is lower than the tire requirement, then the tires will not inflate completely. For instance, if the tire requirement is 75PSI and the compressor is rated at 70PSI, you will only achieve up to 70PSI as maximum operating pressure.
It is advisable to pick an air compressor with at least 10PSI higher than the tire requirement. While an equal rating between the tire and the compressor may work, it may fill up slower as you approach the maximum inflation pressure.
Most auto professionals recommend a compressor with about 90PSI tank pressure to ensure that your car gets adequate pressure. However, most car only require up to 45PSI. Cold tires could require a little less pounds of pressure because of the pressure drop phenomenon. So, except if you have to use the air compressor for your RV or huge truck, there is really no need in worrying about the maximum operating pressure of the air compressor.
Once you are sure that the compressor pump can produce enough pressure, the next consideration is the cubic feet per minute (CFM) rating. This rating shows the rate at which air can flow from the compressor. A higher CFM air compressor rating means that the device can fill up the tires faster. Unsurprisingly, you would often have to pay higher for such an air compressor. Usually, a car tire will inflate well from a compressor with airflow of between 2 and 3 CFM.
Tank Size needed
Air compressors for filling car tires come with tanks for storing pressurized air. The size of this tank matters. With a large tank, the air compressor can stay for long before it cycles again. Smaller tanks are ideal for portability.
The amount of air pressure required would determine the suitability of any air compressor tank size. If you are only topping off your tires, a 1.5 gallon tank should be enough. However, filling the tires from scratch would require a much larger tank. A smaller tank would require more time because of the several cycles required. If your car has larger tires, you want to invest in bigger products such as portable 3-gallon and 6-gallon compressors.
The duty cycle of an air compressor is the amount of time it can work before it switches off to cooling mode. Often, the duty cycle is given as a percentage. Compressors come with a thermal protection feature that switches off the unit at a certain temperature. For air compressors that don’t have thermal protection, it is upon the operator to switch off the machine to prevent overheating.
Duty cycle and tank size go hand in hand; a larger tank gives the compressor pump ample time to cool and therefore minimize chances of wearing/overheating. Not all small air compressors need to rest a lot. Most portable air compressors that are designed for use with cars are capable of running continuously for extended periods.
Cord & Hose Length needed
The performance of the air compressor can be affected by the length of the hose and power cord. You could go for 60-meter long hose to reach any corner you wish – but that can have drawbacks. Inconvenience aside, a too long hose can cause slight loss of air pressure in the tire air compressor.
As for power cord, it is advisable to avoid extension cords because they can cause motor issues. It is often easier to take the compressor to the tires than vice versa. You will be pleased to note that there are several battery powered air compressors in this regard.
There you have it! The most important factors when considering the best size of air compressor are inflation pressure, CFM compressor, tank size, duty cycle and cords with air compressors. There are many more factors beyond these, but they mostly serve to make the job of the portable air compressor more efficient and comfortable.
Hopefully, you are now on the path to owning the best size of powerful compressor to fill car tires, ready to hit the road any moment. Don’t forget to check for proper air pressure with the help of a pressure gauge and using the manufacturer’s recommended PSI of pressure as a guide. If this article has increased your confidence as you shop for the product, please remember to share it.