What your customer needs to know
about towable air compressors

Towable air compressors are self-contained packages that provide efficient, dependable power for a wide range of air-operated tools and equipment - breakers, hammers, tampers, drills, chipping guns, sandblasters, painting equipment and various hand tools.

Compressors are a familiar sight on road construction and maintenance projects, on bridge building and repair jobs, and are needed for most general construction and for maintenance projects. They also are used to clean out piping systems, such as sprinklers and irrigation.

Renting a compressor often offers you the opportunity to rent tools along with the air unit. While contractor customers usually own a good selection of air tools, compressors often are rented when all available tools are in use during peak workloads. It always is a good idea to ask customers if they need extra tools.

The most popular sizes of air compressors can be towed easily by a pickup truck and are easy to maneuver on job sites. Towable models range in capacity from about 70 cfm to 800 cfm, but compressors in the 90- to 375-cfm range are in highest demand at rental centers. The operating weight of smaller towable units is about 1,200 pounds; larger compressors weigh more than 5,000 pounds.

Basic components include the power source, the compressor element, cooling system, canopy, frame and undercarriage, and towing package. Most compressors are powered by a gasoline or diesel engine, but units that operate on compressed gas also are available.

Capacity is measured in cubic feet per minute of air produced (cfm).

Who rents towable air compressors?
Towable air compressors primarily are contractor rentals. Homeowners' needs usually can be accommodated with smaller, portable models. But there are occasions when a towable unit can be the best value for a homeowner project, so it's important to work with the customer and identify the intended use of the equipment.

Towable compressors are standard equipment for general contractors and contractors specializing in paving and bridge construction and maintenance, homebuilders and firms that construct commercial and industrial complexes, landscape contractors and park maintenance departments, utility companies and contractors who serve them, industrial plants, municipalities, military and governmental agencies, and local, county and state street and highway departments.

Operation
Modern air compressors are extremely user-friendly, even for first-time users. Controls are easy to understand and use and gauges help operators monitor operation. Decals serve as a reference to key functions.

Renters always should be briefed on how to start and stop the unit, and how to hitch the compressor to the tow vehicle correctly. The third wheel or stand must be raised before the unit is towed. Review specific procedures for the unit being rented and send a copy of the manufacturer's manual with every compressor that goes out. Make sure the renter understands what type of fuel the rented unit requires.

Safety
Begin safety instruction with a review of preparations for towing. Show the renter how to confirm that connections are made properly and where to attach safety chains. If the unit is equipped with lights, they should be connected.

Never operate a compressor in enclosed or unventilated areas.

GrimmerSchmidt Compressors, Franklin, Ind., has developed an easy-to-understand, single-page summary of key operational and safety points. It is laminated and has a grommeted hole, so it can be attached to compressor equipment. It says:

• Park a compressor on level ground and block wheels.
• Use hoses with safety lock or pin connections, and use only hoses adequate for equipment capacity.
• Always wear eye protection.
• Never breathe compressed air or direct the air supply at food; compressor air is not suitable for human consumption.
• Never point air at any part of your body or at another person - the high-pressure force actually can kill.
• Do not readjust or restrict pressure-relief values or make adjustments to shut down sensors or switches.
• Equipment should not be refueled or serviced while the engine is running, and components should be allowed to cool before performing maintenance.
• Hoods, canopies and covers should be shut or replaced and secured after maintenance, and remain closed during operation.

Maintenance on the job
Equipment on short-term rental should require no on-the-job maintenance other than refueling and checking engine oil and cooling system fluid levels. Advise customers of the type of fuel and oil that should be used. Longer-term rentals may require routine maintenance at frequencies recommended by the manufacturer.

Engine oil should be changed at prescribed frequencies - whether by the customer or rental center.
Filters may need to be cleaned or changed, and the cooling system may need service, especially in hot working conditions. If oil is being discharged with the air supply, check the separator valve and replace if necessary.

Note: before performing maintenance, always relieve receiver pressure and allow time for cooling.

Comments from the industry
Atlas Copco, Holyoke, Mass., Paul Lusignan, product specialist, light construction equipment: "Use good quality fuel and use proper containers for storing fuel supplies and filling the unit. Safety: remember that a compressor is a piece of equipment that operates with discharge pressure from 100 to 350 psi [or more]."

DiStefano Sales Co., Franklin Park, Ill. (LeRoi compressors), Robert DiStefano, vice president &shyp; sales: "Problems a customer might encounter during use are overheating and oil blow-by. For overheating, coolers should be cleaned and filters checked. The separator should be replaced if air has oil in it."

GrimmerSchmidt Compressor, Franklin, Ind., Kevin Burdine, portable sales: "Customers should be instructed to check engine oil and coolant levels, fuel and maintenance indicators daily. Before transporting, hitch bolts and tire pressures should be checked."

Mitsui Machinery Distribution, Bridgeport, N.J., Mark Britt, product manager: "Air compressors of the future will need to meet new regulations on emissions and noise levels. Horsepower limits will require manufacturers to develop new designs."

Rand Equipment Division of Ingersoll-Rand Co., Mocksville, N.C., Joe Jabbour, sales manager: "Renters should be instructed to observe the equipment's diagnostic panel for indications of shutdown. They should observe operating conditions and report detailed information as necessary to rental store service personnel."