EMAX Air Compressors

Two-Stage Piston or Rotary Screw: Choosing an EMAX Air Compressor

EMAX builds two compressor designs. The right one depends on how many hours a day your air system runs and how steady the demand is.

• Two-stage piston compressors use cast iron pumps such as the APP4V1043TP and APP2I0524TP and reach a maximum of 175 PSI. They are rated for a 60% duty cycle, and many pressure-lubricated models are listed as continuous-run capable. They suit auto repair bays, body shops and fabrication shops where air use comes in bursts. Two-stage models list ETL, ASME and CRN in their product data. Browse them in EMAX two-stage piston air compressors.
• Rotary screw compressors are oil-injected, single-stage units rated for up to 100% duty. Most models reach a maximum of 145 PSI, and the ERVK100001 reaches 167 PSI. Many include an integrated refrigerated dryer and an automatic dual-timer tank drain, and many are UL listed. Product data lists a noise level of 62 dB(A) for the ERVK070003-460 and 64 dB(A) for the ERIK010001. These units fit production lines and shops that run air tools for long stretches. See EMAX rotary screw air compressors.

Horsepower and CFM: Sizing an Industrial Air Compressor

Start with air demand, not horsepower. List the tools that run at the same time, look up each tool's CFM requirement and working pressure in its manual, and add them up. Then choose a compressor whose rated CFM covers that total with a margin, because hoses, fittings and future tools all add demand. The table below summarizes the main EMAX configurations in our product data.

The splash-lubricated ESS models are rated differently. The ESS07V080Z1 has a three-cylinder pump rated 35 CFM (30 CFM at 175 PSI) and is noted as not rated for continuous-run service. The ESS07V080Y1 is rated 26 CFM (24 CFM at 175 PSI). The ESS models list an estimated pump life of 50,000 hours, compared with 70,000 hours for the pressure-lubricated two-stage pumps. For rotary screw models, estimated air-end life is listed as 100,000 hours on ERVK models and 60,000 hours on ERIK models.

80 Gallon vs 120 Gallon Air Compressor

The tank stores compressed air, so the pump cycles less often and short spikes in demand are covered. EMAX two-stage models come with either an 80-gallon or a 120-gallon vertical tank at the same horsepower and CFM, so the choice is mostly about stored air and floor space. A 120-gallon tank gives more reserve for paint booths, long sanding runs or several users at once. An 80 gallon air compressor fits better where ceiling height and floor space are tight. As a reference, product data lists unit dimensions of 39" L × 25" W × 75" for the ESS 80-gallon models and 44" L x 31" W x 80" H for the 7.5 HP 120-gallon two-stage. All EMAX rotary screw models use a 120 gallon horizontal tank, and the ones that list a weight show 660 lb. When you measure, leave room for service access and airflow around the motor, and confirm your floor can carry the unit's weight.

Single-Phase vs Three-Phase Power

Match the compressor to the power your building actually has. Single-phase 230V models work in shops without three-phase service, but they draw more current. For example, the 10 HP single-phase two-stage lists 52.9 A full-load amps and a 60 A recommended breaker. Three-phase versions come in 208–230V and 460V, and the same 10 HP two-stage at 460V lists 14.1 A and a 25 A breaker. Many models include a magnetic starter, and the ERVK070003-460 rotary screw uses a Wye-Delta start. Product data notes that the recommended breaker size is a guideline. Have a licensed electrician size the wiring and protection to local code, and follow the manufacturer's instructions.

EMAX Air Compressor Oil, Parts and Care

Use the oil type and change interval given in the EMAX air compressor manual for your model. Product data lists these oil capacities: 2 quarts for APP4V1043TP pumps, 1.75 quarts for APP2I0524TP pumps and 1.33 gallons for rotary screw models. The service kits named in product data are EFKIT008AWBS for many two-stage models and SKIT001AWB for many rotary screw models. General care tips:

• Check the oil level before each shift and look for leaks.
• On manual-drain models (ES and ESS series), drain tank condensate daily. On other models, check that the automatic dual-timer drain is cycling.
• Inspect belt tension and wear. Most models use two belts, and many include a belt tensioner.
• Keep intake filters clean and install the unit in a dry, ventilated spot.

More Compressors from Vovlift

EMAX covers stationary shop air. For smaller jobs, our Compressors category includes diaphragm compressors and air-line couplers from other brands. Whichever unit you choose, follow the manufacturer's instructions and your site's safety program for installation, pressure settings and maintenance.