Every chilled water system needs a pump to circulate the coolant. Understanding how centrifugal pumps work — and which pump is right for your application — is a fundamental part of designing a reliable process cooling system.

How Centrifugal Pumps Work

A centrifugal pump uses a rotating impeller to create flow. Liquid enters at the center (the eye of the impeller), is accelerated outward by centrifugal force, and exits through the discharge port at higher velocity and pressure. An electric motor drives the impeller, typically via a direct-coupled or close-coupled shaft.

The result is continuous, smooth flow — well-suited to chilled water recirculation where consistent pressure and flow rate are more important than high head pressure.

The Rite-Temp Pump Lineup

Rite-Temp stocks and sells two primary centrifugal pump lines, each suited for different applications.

Berkley SSCX — Stainless Steel Series

The Berkley SSCX is a general-purpose stainless steel centrifugal pump built for applications requiring corrosion resistance. Stainless construction makes it well-suited for food and beverage applications, brewery glycol systems, and processes involving corrosive or high-purity fluids. Rated to 185°F and 125 PSI, available from ½ to 2½ HP. Three mechanical seal options available. Stocked for fast availability.

STA-RITE J/JB Series — Cast Iron High-Performance

The STA-RITE J and JB series are heavy-duty cast iron pumps for high-head industrial applications. The J series is rated to 140 ft of head at 90 GPM; the JB offers 110 ft at 140 GPM for higher-flow applications. Cast iron construction at a lower cost point than stainless — appropriate for closed-loop systems where fluid quality is controlled and corrosion is not a concern.

ODP vs. TEFC Motors

All Rite-Temp centrifugal pumps come standard with Open Drip Proof (ODP) motors — suitable for clean, protected indoor environments. The motor is open to ambient air for cooling, which makes it efficient but vulnerable to dust, moisture, and harsh conditions.

For outdoor installations, wet environments, or dusty industrial settings, specify a Totally Enclosed Fan Cooled (TEFC) motor as a special order. TEFC motors seal the motor windings from the environment, adding durability and weather resistance at a modest cost premium.

Sizing Your Pump

Pump sizing for a chilled water system requires matching two key parameters:

• Flow rate (GPM): Determined by your chiller's heat load and the required temperature differential. A common starting point is 2.4 GPM per ton of chiller capacity at a 10°F ΔT.
• Head pressure (ft or PSI): The total pressure drop of your chilled water loop — including pipe friction losses, heat exchanger pressure drop, valve losses, and elevation changes. Size the pump to overcome total system resistance with enough margin for flexibility.

Not sure which pump fits your system? Call Rite-Temp at 1.800.462.3120 — we can help you calculate the right flow and head requirements for your application.