If you’re in the market for towable air, a 185-cfm unit is likely near the top of your list. One of the most popular sizes of portable air compressors, these flexible models are a go-to for running multiple pneumatic tools, irrigation blowouts, media blasting and much more.
How to decide on a 185-cfm air compressor? There are a few questions to keep in mind. First, what tools will the compressor primarily be used to operate; how much cfm and what working pressure are required for the tools and application; and how many tools will be used at the same time? Only then will you move on to considerations such as features, service and support.
When you’ve targeted the 185-cfm as the size that best fits the needs of your applications, there’s still a lot to take into account. “It’s a sweet spot in that size class,” says Cody Blythe, product manager for Doosan Portable Power. “When purchasing a small air machine, a big consideration is the total cost of ownership, and another is the resale value.”
Attention to these customer concerns, Blythe says, is often part of the design process. For example, many manufacturers now try to make oil change intervals and consumable items last as long as possible to reduce cost. They’ve improved ease of service and access prompted by increased labor rates at dealerships. Machine makers have even focused on boosting resale value by looking at the construction of the machine. For example, choosing a brand that has designed longevity into the unit by using materials such as galvannealed steel that inhibits rust increases resale value over time.
Regardless of resale value, robustness should be a key feature, as these units are often used in demolition work, and with a variety of air tools for concrete and asphalt removal.
“Ruggedness and durability reign supreme, due to the often punishing conditions these machines endure,” says Chance Chartters, national sales manager for Mobilair products, made by Kaeser Compressors. “Compactness, maneuverability and roadworthiness are also valued.”
Chartters says end-users also find fuel efficiency and low noise particularly valuable, and points to Mobilair’s polyethylene doors, which are lightweight, but durable against damage and corrosion, and feature a double wall design to suppress noise.
With a range of options available, how has the 185-cfm air compressor retained its popularity over the years? For many contractors, size matters. “It’s easily towable, so there will be less logistics cost,” says Clayton Jones, product marketing manager of portable air at Atlas Copco Power Technique. “It tackles a range of applications when other size compressors will be too big.”
It could be because it’s still the best compressor for running two larger pneumatic tools, such as 90-lb breakers or mid-size rock drills, says Eric Massinon, business development manager at Chicago Pneumatic Power Technique.
“In the late 1980s, the rental industry for compressors was much different,” Massinon says. “Rental companies used more compressors, and the fleets consisted of the 100-cfm single tool compressors and the 185-cfm two tool compressors. The change occurred when the price of the single tool compressors was only $1,000 less than the two tool compressors. At this point, the larger rental companies started standardizing on purchasing only the 185-cfm two tool diesel compressors.” Massinon notes that, with an increased price on 185-cfm units since that time, rental companies should start looking at adding the single tool diesel compressors — which offer many advantages — back into their rental fleets. Chance Chartters, national sales manager, Kaeser Compressors, says the 185-cfm unit’s versatility is a key consideration. “It’s been the go-to size for many years,” he says. “While many users do not necessarily need to operate two breakers simultaneously, having that option was important. This size has dominated the portable compressor market because of its versatility in general construction needs.”
Massinon says that contractors became accustomed to asking for 185-cfm compressors. “We trained the industry for over 30 years to ask for a 185-cfm compressor even if they were only running one tool,” he adds. “This is why the 185 is the most popular size.”
Noise suppression is a critical feature, particularly when working in neighborhoods or near other sound-sensitive areas. Eric Massinon, business development manager at Chicago Pneumatic Power Technique, recommends paying careful attention to the sound suppression features on the compressor you choose. He says to look for a quality enclosure with real sound suppression and suitably protected surfaces. “When looking at a compressor, you can see on the hoods, end panels and side doors if the manufacturer is using properly designed louvers for sound suppression or stamped-out holes in the panels for the air flow,” he says. “The stamped-out holes offer no sound suppression.”
Massinon also places importance on the oil-flooded rotary screws used in the compressors, noting that there is a difference between using tapered roller bearings in the construction of the airends and true roller and ball bearings that are properly sized for the load.
Although useful as a multi-purpose bearing such as on a wheel, taper bearings are not the best choice for this application. Massinon says roller and ball bearings sized for the loads create less heat, less load and will operate longer than a taper bearing, resulting in fuel savings by decreasing the load on the engine.
Dependability is a theme also echoed by Sullair. Jerel Cole, senior product manager, says their customers focus on performance and reliability. “They seek a dependable workhorse that can get the job done,” Cole says. “Our airend — the most important part of a compressor — is known to be long-lasting and many customers often refer to our airends as bulletproof.”
Rental Run Through
If you have no need for a 185-cfm air compressor on a full-time basis but want to make sure you’re getting the most out of a rental unit, your rental house can definitely help you out, as they are the primary purchasers of these size machines.
“In the past several years there are more and more players with 185-cfm air, and yes, all rental houses will have some kind of a fleet of 185-cfm units,” says Clayton Jones, product marketing manager of portable air with Atlas Copco Power Technique. “Always know the specs of the application and if the 185-cfm will tackle the task.”
In addition to understanding if the compressor will meet the air flow requirement to run the tools for the job, the unit you rent should be easy to operate, and you should know how much fuel it consumes. Whether you’re renting the compressor for the week or for the season, do your homework. “An oversized compressor will be costly to operate and reduce your return on investment,” says Cole. “Too small of a compressor will have a negative impact on productivity.”
Chartters, who says demolition and civil construction contractors are heavy renters of this size compressor, also says rental store staff is generally knowledgeable in air compressor sizing and can help match the compressor to the job. However, selecting the compressor doesn’t end with right-sizing, he says. “You should also do a walk around to make sure the unit is in good working condition and safe to tow, starts easily, has tires fully inflated, the lights work and the canopy is secured. If you have any doubts about its readiness, ask the staff.”
Amy Materson is a freelance writer for Compact Equipment.
Head-to-Head: Towable vs. Vehicle-Mounted
Towable units have been popular for years, based on their proven reliability. However, in recent years, vehicle-mounted compressors have gained some popularity based on constant availability and ease of transport. Even so, tow-behind compressors maintain huge popularity with both buyers and renters due to a range of factors.
“While truck-mounted compressors are gaining ground among those buying to own and operate them, towables will continue to dominate the industry because most are rented,” says Chance Chartters, national sales manager at Kaeser Compressors. Installing the compressor on a truck is not suitable for most rental applications due to the extra time and special equipment needed to place it. Further, the renter’s vehicle would have to be prepared for it.”
Practicality seems to be the primary reason towables will remain popular into the future. “Towable is flexible,” says Clayton Jones, product marketing manager of portable air at Atlas Copco Power Technique. “If there are operational issues, it is much easier to swap than a fixed mounted unit.”
Also, many contractors do not use the compressor on a daily basis and would not want to tie up a truck with a vehicle-mounted unit, says Cody Blythe, product manager at Doosan Portable Power. “Most compressor manufacturers offer the small towable units in a truck mountable configuration from the factory or have aftermarket kits available to convert them to a truck mountable unit,” he says.