This article covers the two types of priming systems offered by Waterous: Electric and Air Primers.

What is Priming?

Before any centrifugal pump can be operated, it must be primed. Priming is the process of replacing air in the intake lines and portions of the pump with water. If the pump is to be operated from draft, priming must be done by means of a positive displacement pump, or some other device for creating a partial vacuum. Also, when pumping from a water tank, priming will be accomplished more quickly and positively if a priming device is used. Priming will occur naturally when pumping from hydrants or in relay, because inlet water pressure is high enough to force air out of the pump and intake lines, providing a discharge line is opened to permit the air to escape.

Electric Primers:

An electric primer uses a small size vacuum pump or self-priming pump or a positive displacement pump to prime the fire pump. The basic system consists of an electrically operated, oil-less, rotary-vane positive displacement vacuum pump powered by the truck’s electrical system, priming valve, an auto or manual-prime control panel and optional primer lubricating oil reservoir. The suction line of positive displacement pump is connected to the discharge line of centrifugal pump. This positive displacement priming pump evacuate all the air in the pump and suction piping.

Air Primers:

An air primer system uses the on-board air supply to create a vacuum to prime the fire pump. The basic system consists of an air primer, a priming valve, an auto or manual-prime control panel, and a compressed air supply equipped with a pressure protection valve. Additional components, or a combination of components, allow you to operate the system from multiple locations and prime multiple locations individually or simultaneously.

What Primer Should I Use?

To answer the question which Primer should you use? It depends on your situation and environment. Both perform the same function, priming the centrifugal pump. Both meet or exceed NFPA 1900, Vacuum and Priming Standards, have Optional Auto-Prime features, automatically drain, have 7-year warranties when ordered with the pump and can be pump mounted. Here are the differences that may help you decide:

An electric primer can pull a deeper vacuum in all weather conditions as compared to an air primer.

The air primer uses the apparatus compressed air system therefore does not draw the current that an electric primer requires. An additional advantage of an air primer is that there is no maintenance required, no moving parts and brass body construction.

 

Waterous Offerings

Electric Primers:

The Waterous oil‐free rotary vane primer provides a fast, positive prime. A combination of high capacity and high vacuum producing ability assures rapid priming. This electric motor primer allows you to re-prime while pumping without reducing engine RPM because it does not rely on engine vacuum or exhaust. Electric motor driven primers also may operate with the engine stopped.

Engineered to provide a long operating life, the simple design of the Waterous priming system means fewer moving parts and easy maintenance. Rotating parts in the VPO and VPOS are made of corrosion‐resistant, anodized aluminum, stainless-steel and composite materials.

The VPO and VPOS primers come with a standard 7-Year Warranty can be mounted directly on a Waterous split‐shaft pump transmission or separately mounted in any convenient location.

Vacuum Activated Priming Valve (VAP):

The VAP consists of a stainless-steel valve stem, spring, and pressure disk in a plastic valve body. A rubber disk forms the seat for the valve steam and forms a seal between the priming valve inlet and pump body. A rubber diagram forms a seal which allows the valve to open and close which allows isolating the interior of the priming valve from atmospheric pressure.

A lubrication option allows the use of Prime‐Safe™ lubricant. A priming tank is required when the lubrication option is selected.

Air Primer:

The Venturis Air Priming system uses the on-board air supply to create a vacuum prime to the fire pump. The basic system consists of a Venturis Air Primer, priming valve, and available in auto or manual prime control panel.

Venturis Air Primer:

All brass body construction with no moving parts. No maintenance is required. Comes with a standard 7-Year Warranty and can be mounted directly to your Waterous

Vacuum Activated Priming Valve (VAP):

The VAP consists of a stainless-steel valve stem, spring, and pressure disk in a plastic valve body. A rubber disk forms the seat for the valve steam and forms a seal between the priming valve inlet and pump body. A rubber diagram forms a seal which allows the valve to open and close which allows isolating the interior of the priming valve from atmospheric pressure.