Gorman-Rupp PA6A Prime Aire Priming-Assisted Pump

The Gorman-Rupp PA6A is a 6 x 6 inch solids-handling model of the Prime Aire PA Series, a priming-assisted (dry prime) pump developed for construction sites and now used in municipal and industrial duty. It moves up to 1800 GPM at 152 ft head and passes 3 inch solids, and is offered as a pump end or with an engine drive on a fuel base for sewage bypass and large-volume dewatering.

How the priming system works

Prime Aire pumps do not rely on a conventional self-priming volute. A venturi compressor priming chamber and priming valve use compressed air from an air compressor to create vacuum, evacuating air from the casing and suction line to atmosphere; atmospheric pressure then pushes liquid into the pump. The manufacturer says this removes the leaks associated with traditional priming-assisted pumps, reduces environmental concerns on sewage bypass jobs and lets the pump run under flooded suction without leaking. It suits long or oversized suction lines, intermittent flow and liquid carrying a lot of air.

Technical specification

Features listed for the PA Series

The brochure lists dry-run capability, an oversized abrasive-handling mechanical seal, standard auto-start control, a variety of impeller options, fuel level monitoring on Tier IV engine-driven models, and sound-attenuated or electric-driven configurations on some models. Impeller choices include two-vane ductile iron semi-open impellers for solids up to 4 inch and enclosed impellers for clean water. The Eradicator wearplate with grooves, notches and lacerating tooth is used to break up stringy material, and many Prime Aire Plus models add a side port for inspection and clean-out.

Auto-start controls switch the pump on and off with changing liquid level; a microprocessor engine control monitors engine functions and alarms on a 32-character display. A diaphragm vacuum primer of up to 60 CFM and vacuum to 30 ft is offered as an alternative to the compressor system on selected models.

Neighbouring 6 inch models

For hot-climate sites check engine cooling, fuel base capacity and noise limits with the manufacturer. The brochure does not list approvals for the PA Series.

Duty point in other units (derived)

Unit conversions below are calculated from the printed maximum values and are not manufacturer statements.

The PA6A is typically bought as a complete engine-driven set on a fuel base, but the brochure also notes that PA Series pump ends can be SAE mounted for direct connection to flywheel housings if you already own an engine. Engine choice affects emissions tier and fuel monitoring, so state the required tier and the site noise limit when asking for a quotation. Large air volumes in the suction line are the situation this pump is designed for.

Options, support and what to request

Optional accessories described by the manufacturer include a compressor-over-pump arrangement for a self-contained compact set, an integrally mounted diaphragm primer, auto-start controls and an Eradicator self-cleaning wearplate. Support literature for each pump, including manuals, curves and outline drawings in PDF and CAD form, is obtained through the manufacturer. When you ask for a PA6A quotation, state engine make, emissions requirement, trailer or skid base, and whether a sound-attenuated enclosure is needed.

Frequently asked questions

What does priming-assisted mean?

A venturi compressor and priming valve evacuate air from the pump and suction line, then atmospheric pressure fills the casing, instead of relying on a self-priming volute alone.

What flow and head does the PA6A reach?

The operating range table gives 1800 GPM (114 lps) and 152 ft (46 m) maximum.

Can it run dry?

Yes, the oversized oil-lubricated seal allows continuous dry running per the manufacturer.

What solids size is listed?

3 inches (76 mm) maximum.

What warranty is quoted?

A two-year warranty on PA and PAH Series pumps; confirm with Gorman-Rupp.

Documents and quotation

Brochure: Prime Aire and Prime Aire Plus (AV-05401). See more in Pumps. Seven Star LLC is an independent supplier in Muscat; quote with engine make, enclosure and duty point.