Balboa 1.25 HP ITT Marlow Gemini Plus NR4A-C Bath Pump with Air Switch & Cord

Upgrade your whirlpool or hot tub with the Balboa Gemini Plus NR4A-C Bath Pump — a compact, high‑flow solution built to meet today’s demanding spa jet needs. This 1.25 horsepower pump carries the trusted Gemini Plus lineage into quieter operation and improved efficiency, making it a smart replacement for older systems while delivering powerful, consistent jets for a more premium spa experience.

Why this pump stands out

• Ultra‑compact design fits into tight spaces and virtually any installation, simplifying retrofits and new builds alike.
• Centerline discharge enables flexible plumbing with right‑ or left‑side mounting to suit your tub’s layout.
• Air Switch and Cord included right in the box for easy installation without additional parts.
• Engineered seal design focused on reliability in demanding spa environments, helping minimize maintenance concerns.
• 12.5 AMPS nominal provides robust performance while remaining compatible with standard spa wiring.
• Quiet, high‑flow operation to enhance your soak experience without intrusive noise.
• Optional Digital Variable Speed Control Kit lets you tailor jet flow and noise to your comfort level.

Performance and compatibility

The NR4A-C model is the modern replacement for the original R125A-C “R” series pump. Part of Balboa’s Gemini Plus II family, it delivers improved performance and quieter operation to match today's high‑flow whirlpool jet systems. If you’re upgrading from older equipment, this pump preserves the familiar electrical footprint and mounting dimensions, making installation smoother and downtime shorter.

Use cases and ideal applications

Perfect for mid‑ to large‑volume hot tubs and spas that demand strong, dependable jet power without sacrificing serenity. It’s an excellent fit for retrofits in tubs that previously used the R125A-C, as well as new installations that require a compact pump with flexible mounting options and straightforward wiring.

What you get and how it helps your spa

• Gemini Plus NR4A-C Bath Pump (1.25 HP) for reliable, high‑flow jet performance
• Air Switch and Cord included for immediate, worry‑free installation
• Centerline discharge for easy alignment and flexible plumbing
• Option to add the Digital Variable Speed Control Kit for precise flow control and noise management

Installation tips and care

Thanks to its compact form factor and centerline discharge, this pump accommodates a wide range of tubs and installation configurations. When swapping from the older R125A-C, confirm mounting orientation and electrical compatibility before wiring. For the quietest operation and customized jet feel, consider pairing with the optional Digital Variable Speed Control Kit and tuning the pump to your tub’s jet layout and desired ambiance.

Who should consider this Balboa pump

Homeowners upgrading aging spa systems, installers seeking a reliable, space‑savvy replacement, and anyone who wants a high‑flow, low‑noise pump capable of powering modern whirlpool jet configurations. With included Air Switch and Cord, it’s ready to install in most standard spa enclosures right away.

• This pump comes complete with: Air Switch and Cord.

Note: The original R125A-C "R" series pump are no longer made.

• This 2nd Photo is the replacement pump for that model.

The original Gemini Plus pump combined advanced variable speed technology with superior performance to become the "the choice" of manufacturers for almost a decade. The new ultra compact Balboa Gemini Plus II series now offers improved performance and quiet operation to meet the demands of todays high flow Whirlpool bath jet systems. The compact design of the Gemini Plus II is available in standard configurations, providing a high performance pump that will fit in virtually any installation. Variable Speed Control Option - The Gemini Plus II Series Pump is available with a patented "Digital Variable Speed Control Kit" for the ultimate in control flexibility.

Balboa Gemini Plus II Bath Pumps Feature:

• NR4 12.5 AMPS
• Engineered seal design for maximum reliability
• Centerline discharge allows right or left mounting
• Factory installed cord
• Air Switch