Maintaining and servicing your air compressor properly is mission-critical for getting the most out of your air compressor. Compressed air is the lifeblood of many garage operations.
How do I maintain and service my air compressor? There are 18 steps to properly maintaining and servicing your air compressor, at different points in time:
| Before First Use | 1. Be mindful of the location 2. Check the safety valve 3. Ensure the proper voltage |
| Daily | 4. Check the oil 5. Drain moisture 6. Check the pressure switch unloader valve 7. Make sure the nuts, bolts & screws are tight 8. Prevent overheating 9. Store power cords/air hoses |
| Weekly | 10. Clean the components |
| Monthly | 11. Check the air intake filter 12. Tighten the cylinder head 13. Check belt tension 14. Remove moisture or oil from the air supply |
| Annually | 15. Formulate a troubleshooting checklist 16. Replace the regulator 17. Replace the check valve 18. Store properly |
I have divided the recommended maintenance activities into daily, weekly, monthly, and yearly subsections for your convenience. There are also guidelines for what you should do before even starting your air compressor for the first time. I hope that you will find that this guide helps you towards your quest to get the most out of your air compressor.
Before Operation
These are tasks that should be performed before you even start your air compressor for the first time. These steps help ensure safety.
Be Mindful Of Location
Your air compressor should always be located in an area that is well-ventilated, where it will not accumulate too much dust.
If you have a miter saw or other similar equipment in your shop, it is ideal that your air compressor is located on a different side of the shop.
You will also want to ensure that the compressor is located in an area where adequate airflow will be maintained. For this reason, you will see that most owner’s manuals recommend at least 2 feet of free space around and above the air compressor.
Check The Safety Valve
The safety valve is responsible for keeping the tank of the air compressor from overpressurizing and possibly rupturing or even exploding.
Before even starting your air compressor, make sure that the safety valve on the air compressor is functional, as is stated in the user manual for this air compressor.
To check the safety valve, pull the ring that will typically be located near the pressure gauge(s). Check the owner’s manual for your specific model for instructions.
Be sure to replace the safety valve if it gets stuck or does not operate smoothly.
Ensure Proper Voltage
According to this site, most homeowner-sized small compressors are designed to run on a single 110V outlet while larger compressors offer a choice between 110 to 460 Voltage.
Your air compressor should have its own designated circuit within your home or shop.
If you are using an extension cord, make sure that it is a 3-wire extension cord and is not longer than 50 feet.
Daily Maintenance Activities/Proactive Measures
Here you will find guidance on a variety of maintenance activities you should perform each time after you use your air compressor.
Each time you shut down your air compressor for the day you should:
Check the oil level at the sight glass
If your air compressor uses oil
Drain the moisture from the tank
Ensure that the pressure switch unloader valve is working
Make sure there are no loose nuts, bolts, and screws
Prevent the unit from overheating
Store the power cord & air hose properly
Tighten The Cylinder Head
Below you will find more detailed information on how to keep your air compressor running smoothly from day-to-day.
How To Check The Oil Level In Your Air Compressor
There are many air compressors that use oil in order to regulate operating temperatures and reduce wear. If you happen to own an air compressor requiring oil, you are encouraged to check the oil level after each use.
To check the oil level in your air compressor:
Look for the oil-level sight glass or unscrew the cap to access the dipstick
The oil level should at least ½ of the way to slightly above halfway in the oil-level sight glass or on the dipstick
If it appears that it is time for an oil change in your air compressor:
You can find 100% Full Synthetic Air Compressor Oil here.
Replace the oil in accordance with the instructions in the owner’s manual for your air compressor
How To Drain Moisture From Your Air Compressor
Routine use of the air compressor leads to a build-up of moisture within the tank. Moisture in an air compressor comes from water vapor in the air that cools and is condensed as it moves through the system.
You may notice your air compressor accumulating the most moisture on hot and humid days.
If you do not drain the moisture from your air compressor regularly, then the components of the compressor, including the tank and attached tools, will be subject to damage from rusting and corrosion, as is stated in this owner’s manual.
You do not necessarily have to drain the tank daily, but we recommend making it part of your daily routine to the extent that it becomes second nature. This is especially relevant if you use your air compressor periodically.
To drain the moisture from your air compressor tank:
Locate the drain plug, typically found at the underside of the air compressor tank
Place some kind of a plastic pan or similar device underneath the drain to collect moisture.
In some cases, the drain plug may be difficult to reach
Use pliers as necessary to open the plug
Open the drain plug
Make sure you fully tighten the drain plug when you are finished so that the air compressor does not lose any compressed air the next time you try to use it
How To Ensure That The Pressure Switch Unloader Valve Is Working
The pressure switch valve is responsible for regulating the cut-in and cut-out pressure of your air compressor. The cut-in pressure is the pressure setpoint at which the machine will turn on, while the cut-out pressure is the predetermined setpoint at which the machine will shut off.
The pressure switch helps maintain the pressure you receive from the compressor and keeps the compressor from getting damaged from running too hard.
The cut-in/cut-out pressures are set by the manufacturer. The owner’s manual should tell you what the lower and upper pressure setpoints are. For example, the owner’s manual for this California Air Tools Ultra Quiet & Air Free Compressor shows that the cut-out pressure is 120-125 psi and the cut-in pressures between 90-95 psi.
This means that when you first turn on the air compressor, it keeps running until the pressure gauge shows the cut-out pressure. The machine should not turn on again until the cut-in pressure is reached.
Be sure to routinely inspect the system by making sure that the machine is turning on and off at the selected pressure setpoints. Your machine should not constantly be turning on and off. This puts you at risk of burning your air compressor motor.
If an air compressor is turning on and off, the culprit may be the pressure settings, the pressure switch itself, or an air leak in the system.
Make Sure There Are No Loose Nuts, Bolts and Screws
A loosened nut, bolt and screw is an easy fix as long as you are able to catch it before it leads to more trouble.
Before starting your air compressor, make sure that all the nuts, bolts and screws have been tightened very well. This is especially important before your first use or after you have swapped out parts to make a repair.
Keep your ears open to unusual noises or vibrations while you are operating. Sometimes the issue is as simple as a bolt that needs to be tightened a few turns.
Prevent The Unit From Overheating
Air compressors will typically have some kind of a thermal overload protector, as is described in detail in this owner’s manual.
The purpose of the thermal overload protector is to automatically shut the machine off if it becomes too hot.
If the thermal overload protector shuts your air compressor off, follow these instructions straight from the manual:
Physically set the ON/OFF switch to the OFF position
Even if the compressor has already automatically shut down
Unplug the unit
Allow the motor to cool
Then plug the power cord back in
Turn the compressor back ON
Ensure that thermal overload doesn’t occur by placing your air compressor in a location where it will not overheat, as discussed in the opening subsection of this article.
You can also decrease the odds of this occurring by placing your air compressor within a shop where the interior temperature is regulated.
How To Properly Store Power Cords & Air Hoses
If you don’t store the power cord properly, it can become subject to nicks and stretches that will eventually render it useless. There is no reason for your power cords and air hoses to become parts of your air compressor that you have to replace frequently.
First, disconnect the power cord and air hose at both ends. Then you will:
Take the end of the cord/hose in hand and let it hang over your hand in such a fashion that it forms a small coil.
Then quickly reel the rest of the cord into the coil,
make sure to leave a little bit of the cord length out of the coil at the end
The extra cord length at the end of the coil will then be wrapped around the center of the loop leaving 6” or so of extra cord length unwrapped
The 6” or so unwrapped cord length will then be pulled through the upper portion of the coil
You should be able to store the power cord and air hose on a hook near the compressor
This procedure is made much clearer in this video. Other methods for wrapping your air hoses and extension cords are also discussed in the video.
You may have heard of other methods for wrapping cords that have proven successful. Regardless of which specific method is used, it ideally should be performed after each use of the air compressor.
Weekly Maintenance Activities
Make Sure The Components Are Clean
You should perform a general cleaning of the air compressor at least once a week to prevent dust and grime from clogging critical components of the air compressor.
When you do clean your air compressor, it is important that you use:
Either a soft brush such as a utility scrub or a wet cloth such as this microfiber towel
If you are using any solvent other than water, you are encouraged to use a biodegradable cleaner such as Dr. Bronner’s Sal Suds
Monthly Maintenance Activities
These activities need not be performed every time you use your air compressor. You should be performing the actions in this section at least once a month.
Check The Air Intake Filter
The air filter on your air compressor is responsible for reducing the noise and preventing particulates from entering the air compressor.
The air compressor can become damaged if particulates are allowed to enter the air compressor.
Eventually, the air filter will become clogged with dust, and start becoming less effective. The air compressor must be checked and cleaned every now and then, potentially monthly or even more often, depending upon use.
Typically, you can remedy the situation by simply cleaning the air filter with a brush or vacuum. If the filter is clogged, the most viable solution may be to get a new air filter.
Tighten The Cylinder Head Of The Air Compressor
The bolts on the cylinder head of the air compressor need to be checked and retightened at least once a month, or every time the compressor is serviced.
These bolts become loose due to the normal vibration of the machine. Tightening the bolts on the cylinder head requires the operator to follow the procedures that should be outlined
in the owner’s manual for your specific air compressor.
Instruction manuals such as the one for this air compressor will include steps on which order to follow when tightening the bolts, and the magnitude of the torque number and rotational degrees should be achieved.
Failure to adjust the bolts on the cylinder head to the proper tension can cause debris and solvents to make their way into the cylinder bore, among other potential issues.
Use a torque wrench such as the epauto ½” drive click torque wrench to adjust the bolts in the order that is recommended by the manufacturer in the owner’s manual. You will also need to perform these procedures if you need to replace a broken cylinder head.
How To Check for a Leak in Your Air Compressor- With Soapy Water
A convenient way to check for small leaks involves pouring a little bit of soapy water on the area that you think may be leaking air.
Pour or spray the soapy water on the area of interest while the compressor is running. If bubbles start to form, then you will know that there is a leak coming from the area.
13. Check Belt Tension(Reciprocating Air Compressor)
If you own a reciprocating air compressor, such as the Quincy QT-54, then your monthly maintenance activities will include checking the tension of the belt and ensuring proper pulley/sheave alignment.
If the belt tension is off, even by just a little bit, you will run into a number of issues, according to the owner’s manual:
Motor Overloading
Excessive Vibration
Premature Belt & Bearing Failure
When you are performing your monthly inspection of the motor pulley and compressor sheave assemblies, look for nicks or burrs.
Other things to be on the lookout for:
Make sure every component is securely fastened
Make sure that the Compressor Sheath is aligned with the Motor/Engine Pulley
Then measure the belt tension in accordance with the instructions in the owner’s manual for your reciprocating air compressor.
How To Replace The Belt On Your Air Compressor
If you find the belt to be a bit worn during your monthly inspection of the belt components, you will be able to replace the belt with little effort.
Air compressor belts are not universally-sized, so you will need to look up the specific part number to get a belt that fits your air compressor.
Once you know the part number from the owner’s manual, you will find a wide array of options available online, as is the case with this belt that fits many models of air compressors across quite a few different brands.
Replacing the belt is as simple as this:
Unplug the compressor from the wall
Drain all the air out of the compressor
You may need to remove a top cover or belt guard to access the belt
To remove the belt, rotate the flywheel around
When you install a new belt, place the belt around the flywheel first and then position it over the motor pulley
These instructions are generic instructions pulled from a video on how to replace the belt on a specific make and model of air compressor.
You may be able to find similar videos online, including instructions on how to replace the belt on the air compressor you have. You should also be able to find instructions from the manufacturer of your air compressor. Check the owner’s manual before proceeding.
14. Remove Moisture Or Oil From The Air Supply
Air compressors are quite versatile as they are able to supply pressurized air to a variety of attachments and pneumatic tools such as nail guns and paint sprayers.
Unfortunately, pneumatic tools do not usually respond very well to excessive amounts of moisture present in the lines of air compressors.
Excessive moisture in air compressors can even lead to damage and premature failure of pneumatic tools, according to Hydraulics & Pneumatic Magazine.
Moisture is of particular concern if you are using a paint gun with your air compressor. Excessive moisture can find its way into the lines of your air compressor and may ultimately find its way into the paint and contaminate the paint.
Methods For Removing Moisture From The Air Lines
First off, there are a couple of risk factors that will contribute to excessive moisture in the lines of your air compressor:
Operating in humid conditions
Operating for long periods of time, causing the air in the lines to become hotter
The type of compressor you are using
Separator And Desiccant System
Air compressor dryers come in handy, particularly if you are using a piston-driven air compressor. Affordable options include the Edge Industrial Desiccant Dryer and the T-H-B CO Industrial In-Line Particulate Filter.
For added assurance, you can find a dryer and air filter combo, such as the Campbell Hausfeld Air Cleaner, Air Dryer.
The desiccant dryer is installed at a point within the air compressor lines, typically on a wall next to the compressor itself, as is seen in this video.
Servicing Your Air Compressor Yearly
These actions may need to be performed at least once a year or so.
15. Formulate A Troubleshooting Checklist
It is important to have a troubleshooting checklist for your air compressor so that you can take care of the real problem and not spend money on parts that you don’t actually need.
You can get a good idea of the repairs you may need to perform by viewing the owner’s manual for your air compressor, which should have sections on both maintenance and troubleshooting.
As an example, this owner’s manual by DeWalt features a detailed troubleshooting guide showing the most common malfunctions, their causes, and the corrective actions that must be performed.
According to the guide, there are many common causes of air leaks:
Fittings not being tightened all the way
A defective air tank
Leaking seals
A defective safety valve
Holes in the air hose
To ensure that you will cover all bases when you are troubleshooting, take a good look at the troubleshooting guide and make yourself a checklist of each possible cause.
Once you have inspected a component and determined that it is not causing the problem, you
can scratch it off your list and move onto the next potential cause.
16. Replacing The Regulator
The regulator of the air compressor is the control valve responsible for maintaining the desired pressure. The regulator is the plastic knob located at the manifold of the compressor, by the pressure gauge(s).
Eventually, the parts of the regulator will become worn down, necessitating repair. Repairing the regulator of the air compressor is a straightforward task that does not require a technician.
Signs that your regulator needs to be repaired include:
The leaking of air
Failure of the compressor to adequately adjust the pressure
You can find regulator repair kits such as this one online. Regulator repair kits are not universally-compatible, so check to see that the parts match with your model before purchasing.
Repair kits will typically have the parts of the regulator that need to be replaced most often, such as the:
O-rings
Disk at the bottom of the regulator
Regulator Cap
Spring underneath the cap
Stem underneath the cap
The regulator should not need to be replaced all too frequently, but if you run your air compressor enough, you will eventually have to replace the regulator.
17. Replacing The Check Valve
To either replace or clean the check valve follow these instructions:
Release the air pressure from the tank
Unplug the air compressor
Remove the hose to access the check valve
Use a socket wrench to unscrew the check valve
A properly functioning check valve has a valve disc that moves freely within the check valve
The spring should also be able to hold the disc in the upper, closed position
The check valve may not be broken. You can clean the check valve using a paint and varnish remover such as this one
Apply sealant to the check valve and reinstall the check valve
Instructions on which size and type of check valve you need to replace a broken one should be included within the owner’s manual for your air compressor. You can find replacement valves such as the Hromee Air Compressor Check Valve Replacement Kit online.
18. Proper Storage
Before storing the air compressor for an extended period of time, such as several months at a time, clean all dust and debris from the air compressor.
You are encouraged to use an air blow gun attachment to clean the air compressor, as is specified here. In the alternative, you may use a soft brush or wet microfiber cloth.
Then remove the pressure from the tank by pulling the pressure relief valve. Remove all moisture from the tank by turning the drain valve.