How to Read An Air Compressor Gauge

You finally have the right air compressor for your industrial application, and it seems to be working flawlessly. However, unless you understand how to read the pressure gauge on an industrial air compressor, you can’t be sure if it’s doing the job it’s supposed to. If it’s not, you may not find out before it’s too late. Here’s the information you need on how to read an air compressor pressure gauge and what to do if you don’t like what you see.

Industrial air compressors have two pressure gauges that indicate the PSI levels of the two key stages in the pressurization process. The first of these gauges, on the left-hand side, shows the amount of pressure reserved for the tank. The second gauge, which is on the right, shows the amount of pressure that gets generated within the tank.

So what do the two different air compressor gauges mean, and why do air compressors have two gauges? The two gauges of an air compressor are essential for a pair of reasons. On the one hand, each gauge lets you know if the system is healthy. Moreover, each gauge helps you determine how energy gets generated inside the tank for use as air power.

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Why It's Important to Know How to Read An Air Compressor Gauge

Air compressor pressure gauges measure pressure in pounds per square inch (PSI), usually ranging from 0 to around 250, depending upon the machine and the types of gauges on an air compressor. The PSI rating of a compressor indicates the amount of air pressure the unit will generate in a square inch. For example, if an air compressor has a maximum PSI rating of 125, the machine will produce 125 pounds of air pressure per square inch at times of peak performance.

Of course, various factors affect the compressor’s ability to operate at its peak performance level. One crucial factor is the quality of the incoming ambient air, which will only pressurize at 125 PSI if the conditions are favorable from the outset. If the air is humid or dirty as it enters the inlet valves that lead to the compression chamber, the compressor will not be able to pressurize that air to the maximum level indicated on the machine specs.

The purpose of the two gauges is to differentiate the regulation of air pressure sent to the tank from the pressurization intensity that occurs inside the tank. If the pressure of the ambient air is at a favorable level of around 14.7 PSI, the compressor should be able to pressurize this air to the maximum PSI as indicated on the machine.

Therefore, if you wish to run a pneumatic application that requires maximum PSI, you should be able to do so, providing the ambient air is cold, dry and clean. Likewise, if you run several air tools simultaneously and the combined PSI requirements take the compressor to its limits, it should still keep up with your demands as long as the inlet air is favorable.

If the pressure reading on the left gauge is weak, the compressor will not be able to pressurize the air to a sufficient level for your end-point applications. Consequently, you will not see a favorable reading on the right gauge. Ideally, you would be able to use an air compressor regulator according to the needs of your pneumatic applications and have the compressor generate the required level of air pressurization.

For a task like sanding, you would need a constant high level of air pressure. For air-powered screws, riveters and nailing tools, you would need a more moderate level of air pressure, delivered at controlled rates. To meet these needs, the settings on the compressor would need to be within favorable ambient surroundings.

A machine that reads favorably on both PSI gauges will generally be in a ventilated room with relatively cool, clean air. The room should be free of humidity, which makes it more difficult for air to pressurize. Even though most air compressors feature water and oil separators, these components can swiftly become hampered if too much moisture or oily mist enters the machine. The real objective is to keep moisture and dirt levels as low as possible within the ambient air, so the filters and separators can extract what remains of those elements within a healthy ambient setting.

A machine will often give poor readings if the ambient conditions are unfavorable for generating air pressure. For example, if your compressor is in a stuffy room where the air is hot and humid, the inlet valves will not receive air supplies favorable for pressurization. The filters and separators will get overworked when extracting water and oil from the incoming air. Ultimately, the pressurization will become compromised, resulting in insufficient PSI levels in the outgoing air.

For the readings to be favorable on the right gauge, you will also need to have a healthy set of internal factors within the air compressor. In a rotary screw compressor, you will need to have an airtight, rust-free pair of rotors that can rotate adequately. In a reciprocating compressor, you will need to have airtight, rust-free pressurization chambers, and the piston will need to operate at the proper speed. If moving metal parts receive insufficient lubrication, corrosive friction will result. If condensation occurs within the compressor, rust could take root and eat its way through various metal parts.

What Are Proper Air Compression Levels?

Optimal industrial air compression levels will depend upon the size of your air compressor and the specific application in which you are using the air compressor. If you call The Titus Company, one of our experts can help you establish what the right compression levels are for your air compressor.

Air compressors are useful in a range of industries for various applications. In the automotive industry, air compressors power the robotic arms that piece heavy auto-body parts together along production lines. Pressurized air also powers the pneumatic tools workers use to fasten auto parts into place. At the end of the line, compressed air plays a critical role in the sanding and painting functions that place the finishing touches on newly assembled automobiles.

A similar set of complex processes come into play at factories that produce home furnishings and bottled beverages for consumers. For example, a bottling factory will use compressed air to mold each bottle into shape. From there, bottles get filled, sealed and labeled with air-powered equipment.

For large-scale industrial processes like auto assembly and bottling, factories usually use rotary screw air compressors. Rotary screw models draw air through an inlet and pass it through the rotors of two counter-turning screws, which pressurize the air into power. Rotary screw compressors are generally large units that yield maximum PSI levels for demanding applications.

What Are Proper Air Compression Levels?

Large factory settings employ various pneumatic processes with varying needs of time, pressure and consistency. Powering fastening tools requires pressure on a moment-by-moment basis as workers pass successive parts down the assembly line. Applications like air drying, sanding and painting require a more continuous supply of air pressure. Rotary screw compressors are the best option in these environments because the cooling systems in screw compressors come optimized for constant use.

Depending on the number of processes at hand, a factory might need two or three rotary screw compressors of considerable size and capacity. To ensure a nonstop air supply, most factories will have one backup compressor in addition to the one or two primary units that power various pneumatic applications during each shift. For best results, factories place rotary screw compressors in ventilated rooms, sectioned off from the factory floor. Most pneumatic tools receive pressurized air through an arrangement of hoses and tubes that connect to the unit.

Not all professional air-powered processes necessitate the use of large compressors. In auto-repair shops and other small settings, reciprocating compressors are often the preferable option. Reciprocating models are smaller and usually portable units that can fit into narrower spaces.

In a reciprocating compressor, a crankshaft sucks air into the unit and compresses it with a piston within a pressurization chamber. Single-stage models release the air to hoses for use in various end-point applications. In a two-stage reciprocating compressor, the pressurized air moves to a second, smaller chamber for double pressurization at a higher level.

Reciprocating compressors are valuable because of their portability and compactness. However, reciprocating compressors generally require more frequent maintenance than rotary screw models due to the number of internal parts involved.

What Do I Do If My Air Compression Levels Are Too High or Too Low?

If the pressure levels in your air tank are not at the PSI you need them to be, you can adjust the compressor regulator until you are getting the proper flow and pressure. If this does not work, you may need a more powerful air compressor unit, or your unit may need repair.

What to Do If Air Compressor Pressure Is Too High

Each pneumatic tool requires a certain level of air power to work correctly. If you have several tools in use simultaneously, the compressor will operate at a PSI level that accommodates the tool with the highest-pressure application. That can be problematic if a major disparity exists between the highest- and lowest-pressure applications. For the latter use, the excessive air pressure could send too much power through the pneumatic tool in question, which could also prove wasteful from an energy standpoint.

How to Fix High Compressor Pressure

To stop the pressure from overpowering your low-pressure applications, attach your high- and low-pressure tools to different systems. Connect the high-pressure tools to a compressor with maximum PSI, and attach the low-pressure tools to a separate unit programmed for moderate highs.

On a newer system, the easiest way to save energy is to set it for lower pressure requirements. If you operate a multiple-use system with new and old equipment, you might need to retrofit some of your older equipment for lower pressure settings. If it isn’t possible to retrofit specific components, you might need to move those parts to a separate system designed to operate at higher settings when necessary.

To save energy and increase the lifespan of your air compressor, set the system pressure level to the minimum limit required for your operations. Contrary to popular belief, maximum pressure levels do not boost system efficiency. On the contrary, setting your system to its maximum pressure level will merely shorten its lifespan. A minimum setting will save energy and increase the service life of your air compressor.

What to Do If Air Compressor Pressure Is Too Low

When air compressor pressure is too low, it will often be due to an unfavorable set of environmental factors. If the unit is in a humid setting with no ventilation, the air will generally contain too much moisture to pressurize sufficiently. If internal parts within the compressor have eroded because of age or corrosion, that could also be an inhibiting factor.

How to Fix Low Compressor Pressure

To eliminate external factors that might inhibit your machine’s performance, move the unit to an area more ideally suited for an air compressor. For example, if your compressor is currently in a hot, foggy room, arrange a space in a cooler, ventilated area and relocate your compressor to that spot. The air that goes into the compressor should be cool, clean and relatively free of moisture. If necessary, install desiccant air dryers in the room to prevent condensation buildup.

If the pressure is still exceedingly low despite a favorable set of external factors, the issue might be down to the internal parts of your compressor. Inspect the machine for any dirt or problems, such as gunky filters or rusty parts. If a new filter and a clean tray do not do the trick, it may be time to contact a professional.

When it comes to air compressors, The Titus Company has all the knowledge you will ever need. We have been solving compressed air and gas problems for customers in businesses throughout Pennsylvania, New Jersey, Maryland, Delaware and Virginia for over 30 years. We have a wide range of quality air compressors and know how all the best air compressors work, what they can do and how you can best put them to work for you and your business.

If you have any questions at all about air compressors, all you have to do is contact us online today or give us a call at 610-913-9100. We’ll be in touch as soon as possible to answer any air compressor questions you may have.