Nash 904 Series Replacement Pumps

Capacity 4,600 to 28,600 m³/h (2,700 to 16,800 ACFM)

  • Main Features

The NASH 904 replaced the popular NASH CL pump in the 1980’s, and can still be found operating in plants around the globe today. Capacities of the 904 pumps range upward from about 2,700 ACFM at vacuum. These durable pumps can handle excess liquid carryover without any difficulty, even if it arrives as massive slugs. 904 pumps are found in many industries including paper, chemical, and mining.

Key characteristics:

• Demanding environments
• 2in1: pump & compressor
• Reliable and efficient

Engineered for Demanding Industrial Environments

The NASH 904 series offers medium to large capacity, single stage vacuum pumps that are ideally matched to demanding industrial applications and harsh environments. These durable pumps handle excess liquid carryover, including massive slugs, with difficulty and are engineered to withstand demanding industrial applications.

Reliable and Efficient with conical porting and rotor configuration

Patented in 1932, Nash’s conical porting design allows the force of compression to counter the weight of the rotor and shaft to help minimize load on bearings during operation. With constant innovation, Nash’s patented design features:

  • Option for lobe purge to minimize damage from erosion in duties with solids present
  • High liquid carryover tolerance
  • Side discharge to minimize the chance of flooded start
  • Removable bearing brackets
  • Performance test for all pumps


Operates as a vacuum pump and compressor with a discharge pressure range of 30 psia (2.5 bar abs.)

Some applications require vacuum and compression in one process. Instead of handling the gas with two separate machines, our liquid ring vacuum pump and compressor models can do the job with only one pump – reducing cost and simplifying installation.

NASH Classic

With more than 100 years of experience producing liquid ring pumps, we know how to design pumps and compressors that are built to last. As a result, our Classic liquid ring vacuum pumps and compressors, like the 904, are still manufactured by Nash and are running in plants around the world today. Only true Classics manufactured by Nash are 100% performance tested and carry our factory warranty.

NASH 904 models are still available from Nash, the original designer and manufacturer of this popular, and reliable series. Whether you have an existing 904 pump running in your plant that is in need of service, repair, or replacement with a new or NASH Certified™ re-manufactured 904/905 pump, we are here to provide the reliable performance you know and expect from NASH.

Model Numbers

Current Generation




Nash 904 Series Brochure


Nash 904 Series Performance Table